Thermochemical transformations of gadolinium chloride and tetraphenylporphyrin into coordination complexes with imidazole ligands

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Pomogaev, Daniil A. Lukyanov, Elena V. Solovyeva This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7155766/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The electronic structure and thermochemical formation of complex from gadolinium chloride and meso -tetraphenylporphyrin in presence of imidazole molecules were calculated using the Minnesota functionals family, ωB97XD, B3LYP and PBE0 with the relativistic all-electron ahlrichs_x2c vs ahlrichs_def2 with ECP and SDDall basis sets. Enthalpies and Gibbs free energies of all possible formations of ClGdTPP coordinated with different numbers of imidazole ligands (up to 2) and side products were compared. The coordination compound ClGdTPP·2Im was found as the most energetically preferable complex of the discussed reaction in molten imidazole medium at high temperature. Electronic structures and high multiplicities of intermediate gadolinium compounds and final coordination complexes were considered in details. gadolinium meso-tetraphenylporphyrin quantum chemical calculations DFT thermochemistry imidazole Figures Figure 1 Figure 2 Figure 3 Introduction Coordinated metalloporphyrins with lanthanides have long attracted undiminished research activity due to their unique photoinduced chemical and optical properties, which might be applied in various fields of science, medicine and technology. Among the lanthanides, gadolinium is capable of providing the widest range of beneficial properties for medical applications of metalloporphyrins. Its long electron-spin relaxation time, arising due a high number of unpaired electrons opens up the possibility for the use of Gd porphyrins in magnetic resonance imaging especially as necrosis-avid contrast agents [ 1 , 2 ]. Large thermal neutron cross section of 157 Gd isotope, which a natural abundance is about 15.7%, provides a high potential of Gd porphyrins for neutron capture therapy [ 3 , 4 ]. Enhanced phosphorescence of porphyrin complexes with Gd can be utilized for oxygen sensing [ 5 – 7 ]. Altogether, a variety of useful Gd porphyrins properties makes them as promising theranostic agents [ 8 – 10 ]. Coordination of the lanthanides with tetrapyrrole cavity does not proceed easily due to their large radius. Two capable methods for the synthesis of Gd porphyrins are heating of the free base porphyrin with gadolinium acetylacetonate (Gd(acac) 3 ) in inert solvent [ 11 ] or with gadolinium chloride (GdCl 3 ) in molten imidazole [ 12 ]. First method affords the Gd porphyrins with acetylacetonate ligand, which is relatively stable towards the ligand exchange and exists in the monomeric form [ 13 , 14 ], which allows to confirming its structure unambiguously by X-ray diffraction (XRD) [ 15 ]. In contrast, the reaction of porphyrins with GdCl 3 in molten imidazole, which serve in the reaction as both solvent and base, initially affords the product with axial -Cl ligand [ 16 , 17 ], which is quite labile and can be substituted by the -OH group at the treatment of the reaction mixture with water [ 12 ]. Such complexes can associate in the bridged multinuclear structures [ 12 ], which might be the reason why the researchers are unable to grow a crystal suitable for the XRD structure determination. Owing to the structural uncertainty of these complexes, many authors depict their structures without an odd number of charged ligands [ 18 ] or without ligand at all [ 19 , 20 ]. Nevertheless, formation of five-coordinated Gd porphyrins with a single monodentate axial ligand such as Cl or OH is highly unlikely without additional ligands, since the lanthanides tend to form complexes with coordination numbers no less than 6 [ 21 ]. This leads us to assume that imidazole (Im) also acts as an ligand which saturates the coordination sphere of Gd during the complexation with porphyrin, but can leave the complex easily upon an influence of other ligands such as solvents used for the workup. This assumption is supported by the observed phenomenon of reversible Im coordination to the Gd porphyrin in methanol [ 17 ] or Im-HCl buffer [ 22 ]. Moreover, coordination of Im on Gd protects the triplet excited state of the complex, dramatically increasing its phosphorescence quantum yield [ 17 ]. At the same time, the nature of the coordination ligands is often unclear, which impedes the correct interpretation of experimental results. On the whole, the obscurity must not remain for such a promising family of metalloporphyrins obtaining through the widely used synthetic protocol. In the absence of direct experimental data, quantum chemical calculations become the only tool that can shed light on the reaction between GdCl 3 and free base porphyrins in molten imidazole. This study aims to elucidate the Im role in the reaction of GdCl 3 with meso -tetraphenylporphyrin (H 2 TPP) and the structure of the coordination product by DFT calculations of thermochemical parameters of complexation with various numbers of Im ligands in typical reaction conditions of boiling imidazole. The work presents various pathways for thermochemical transformations of gadolinium chloride and tetraphenylporphyrin in molten imidazole into coordination complexes based on quantum-mechanical calculations of vibrational modes and corresponding free energies at the reaction temperature at T = 535K to elucidate mechanism of such conversions when we know only initial reactants and main final products. Energetical preferable reactions were selected among all possible processes involving gadolinium chloride, tetraphenylporphyrin and imidazole at the corresponding conditions. Structural optimization was performed at high spin multiplicity of gadolinium corresponding to the minimum total energy and the scheme of molecular orbital energies are considered including blocks of those almost exclusively formed from f atomic orbitales. Computational methods Optimization and properties calculation of initial reagents (H 2 TPP, Im, GdCl 3 ), final compounds (ClGdTPP· k Im with different numbers of Im moieties, k = 0–2 and side products were performed in the framework of DFT theory. Various functionals and basis sets, the most relevant to the energy-efficient thermochemical reactions of ClGdTPP complexation accompanied by Im moieties coordination were considered. In particular, the following functionals and basis sets were applied for the computational investigation: i) hybrid B3LYP popular for porphyrins study [ 23 ]; ii) MN15, M062X and M06HF functionals family of Truhlar’s group from Minnesota University [ 24 , 25 ]; iii) ωB97XD including both long-range correction and empirical Grimme's D2 dispersion model from Head-Gordon and co-workers [ 26 ]; and iv) PBE0 Perdew, Burke and Ernzerhof hybrid functional for diversity [ 27 ]. Empirical dispersion D3 was applied for all the functionals excluding ωB97XD for the optimization and calculation of complexation energies because it deals with thermochemistry of the macrocyclic aromatic complexes which include heavy elements [ 28 ]. The basis sets choice is restricted by available effective basis functions developed for gadolinium. The following basis sets were tested for various ClGdTPP multiplicities and applied for thermochemical reactions: the hybrid diffused polarization-consistent def2-SVP/def2-TZVP[Cl]/def2-TZVPP-ECP[Gd] (noted as dTP) basis sets of the Karlsruhe group [ 29 , 30 ], Stuttgart potentials SDDall [ 31 ] vs the last decade developed largest relativistic all-electron hybrid ahlrichs_x2c basis sets family (xQc abbreviation) consisting of x2c-QZVPall-2c for Gd, x2c-TZVPall for Cl, x2c-SVP-all for H and x2c-SVPall-2c for the rest elements [ 32 ] which is downloaded from the Basis Set Exchange homepage [ 33 ]. The Gaussian 16 quantum-chemical (QM) package [ 34 ] was used for all calculations. Construction and visualisation of the structures under interest were performed using Gaussview 6 and Chemcraft [ 35 ] sites. The calculations were carried out in Gaussian 16 and optimizations reached all real vibrational frequencies. The calculations of molecular electrostatic potentials and MO delocalization index with f -AO participation percentages were obtained in the framework Multiwfn package [ 36 , 37 ]. Results and Discussion ClGdTPP structure and multiplicity The neutral ClGdTPP complex with various multiplicities was optimized using the Minnesota functionals family M062X, MN15 and MNHF as well as ωB97XD, B3LYP and PBE0 with SDD, dTP, xQc basis sets to verify the most appropriate spin multiplicity m = 2S + 1 for ClGdTPP minimum energies in comparison with other Gd containing compounds [ 5 , 38 , 39 ] (Table 1 ). Gadolinium atom has 7 unpaired electrons on 4f shell which provides the highest multiplicity of ground electronic state with the minimum energy among the lanthanides and all metals in general. Thus, the unpaired f -electrons should provide a group of singly occupied (SO) α molecular orbitals (MO) formed dominantly from f -atomic orbitals (AO) and the corresponding unoccupied β counterparts of low-laying MO energies. Molecular motives consisting of Gd and Cl exclusively define the multiplicity of ClGdTPP and GdCl 3 complexes and their coordination compounds. Table 1 Difference in minimum energies of ClGdTPP and GdCl 3 structures optimized with various multiplicities in respect to the structure with m = 8 ( E m − E m=8 , eV). Multiplicity 2 4 6 8 10 MN15 & xQc 4.30 1.58 1.53 0 1.58 M062X & xQc 7.94 8.01 3.12 0 1.83 ωB97XD & xQc 7.60 2.28 0 1.43 ωB97XD & SDD 7.06 6.55 4.52 0 1.37 B3LYP & SDD 5.43 5.83 4.38 0 1.57 B3LYP & dTP 6.60 6.05 6.90 0 1.60 B3LYP & xQc 5.79 3.35 1.50 0 1.59 GdCl 3 @M062X&dTP 8.23 4.51 0 3.57 GdCl 3 @M062X&xQc 7.67 5.54 3.74 0 3.84 GdCl 3 @ωB97XD&xQc 6.17 5.22 2.88 0 4.33 All the methods provide the total minimum energy for m = 8. The other possible multiples corresponding to the electroneutral compounds have the higher energies. The obtained energy gaps vary greatly between the applied methods and basis sets especially. The closest to the minima is m = 10 for ClGdTPP with energy differences not larger than ~ 2 eV whereas GdCl 3 gives ~ 4 eV. The complexes calculated using the large relativistic all-electron xQc for m = 6 have similar energy difference whereas the other smaller basis sets with ECP provide notably higher values, which are closer to m = 4 and m = 2. The same settings of functionals with basis sets were involved to evaluate structural features of the optimized neutral ClGdTPP complex with multiplicity equal to 8. |Gd−Cl| and |Gd−N| bond lengths, angles between these atoms and non-planarity height h Gd were calculated and compared (Table 2 ). The large ionic radius provides Gd atom to be placed out of the N 4 square plane [ 40 ] and Cl is axially coordinated with the metal atom. The distance between two opposite N atoms and their angle with Gd ∠NGdN reflects a degree of non-planarity h Gd assumed as the N−Gd length projection on the Gd−Cl axis that is a height from Gd to the plane defined as h Gd =0.5|Gd−N|⋅cos(∠NGdN). Table 2 Selected distances (Å) and planar angles ( ° ) in ClGdTPP structure (m = 8) optimized in different methods and bases. functional basis ∠NGdCl Gd−Cl Gd−N ∠NGdN h Gd MN15 xQc 117.4 2.560 2.348 125.3 1.176 M062XD dTP 116.4 2.561 2.331 127.2 1.139 M06HFD dTP 116.1 2.553 2.317 127.9 1.121 PBE0 dTP 116.2 2.544 2.323 127.6 1.114 B3LYP xQc 117.4 2.597 2.365 125.1 1.197 B3LYP dTP 116.7 2.571 2.346 126.6 1.054 B3LYPD dTP 116.8 2.564 2.347 126.4 1.156 CAM-B3LYPD dTP 116.3 2.555 2.325 127.3 1.134 ωB97XD xQc 117.8 2.581 2.357 124.5 1.098 ωB97XD SDD 116.8 2.603 2.334 126.4 1.051 The bond length Gd−N = 2.32 Å measured for GdTPP coordination compound with acetylacetone as an axial ligand [ 41 ] better coincides with 2.317 Å and 2.323 Å distances calculated with M06HFD&dTP and PBE0&dTP, respectively. The only evaluated non-planarity h Gd =1.31 Å is closer to 1.197 Å calculated in B3LYP&xQc but Gd−N = 2.427–2.445Å [ 42 ] or Gd−N = 2.401–2.428 Å [ 43 ] is little bit higher than the maximum bond length 2.365 Å obtained using the same settings. Nevertheless, the other combinations of functionals with basis sets provide also adequate results reasonably corresponding to the experimental data taking into account the errors of measurements and calculations. The Gd out-of-plane height is not less than 1.05 Å which is defined by ∠NGdN between 125°&128° and |Gd−N| in the range of 2.32÷2.36 Å. The coordination bond length between Cl and Gd varies from 2.54 Å to 2.6 Å. Despite the structural parameters calculated in some settings are closer to the know experimental data, reasonable thermodynamics of complexation from initial reagents to final products as well as correct experimental spectral data reproduction are also should be provided that cannot be reached using the same functional and basis sets. Thermochemical process of ClGdTPP formation requires adequate settings to calculate the correct differences of enthalpies and free Gibbs energies resulting in the reaction. ClGdTPP is synthesized from H 2 TPP and GdCl 3 crystalline starting materials dissolved in anhydrous molten Im at T = 535 K where an expected reaction proceeds through the coordination of GdCl 3 with several imidazole molecules which then attack H 2 TPP. The GdCl 3 crystal (space group 176, P63/m) suffers destroying and mixing with other reagents under the high temperature (Fig. 2 ). At the first process of GdCl 3 crystal dissolving, GdCl 3 · 2Im and GdCl 3 · 3Im compounds are formed most probably. The supercell (3×3×3) unpacking leads to the structure with 6 equal bonds |Gd−Cl|=2.82 Å and the crystalline bonds can be broken in two ways, resulting in different GdCl 3 structures, but both free complexes are optimized in the trigonal planar D 3h compound, which can attract several Im ligands from the environment (Fig. 1 ). The Gd complexes are able to coordinate with many ligands, particularly, imidazole moieties that depends on the ligand size, orientation and attachment site, steric and electronic properties. ClGdTPP has five bonds with four nitrogen atoms and one chloride anion and can rearrange into compounds with 6 and higher coordination numbers, through 10 [ 44 ] or even up to 19 as in nanoclusters with GdSn [ 45 ]. This allows predicting ClGdTPP coordination with several Im molecules. GdCl 3 · 2Im and GdCl 3 · 3Im are considered because they are the simplest precursors required for the ClGdTPP formation. Thermochemistry of ClGdTPP·kIm formation Thermochemical analysis of H 2 TPP, GdCl 3 and Im interaction requires a total optimization verified by all real frequencies that allows calculating the difference between standard enthalpies (Δ H = Δ H ° 535 ) and standard Gibbs free energies (Δ G = Δ G ° 535 ) at T = 535 K (the experimental synthesis temperature is 262°C) of reactants and final products. Since only initial reactants and reaction conditions are documented for the experimental procedure of ClGdTPP synthesis but intermediate species are inaccessible, the initial components and final products were considered to model the most energetically profitable reaction pathway and to interpret the obtained results in correspondence with the known experimental data. There is no published data on how many Im molecules can be attached to ClGdTPP and on the exact structure of this coordination compound. Possible ClGdTPP· k Im ( k = 0−2) formations from H 2 TPP and GdCl 3 · i Im ( i = 1−2) are compiled in the general scheme (Fig. 2 ). Final ClGdTPP· k Im are accompanied with several numbers of side products such as single hydrochloride (HCl) and imidazole molecules or their associate. The common formula for all possible reactions with i , j , k , t , m , n = 0−2 expressed as H 2 TPP + GdCl 3 ⋅ i Im + j Im = ClGdTPP⋅ k Im + t Im + m HCl + n HCl⋅Im abbreviated through I ij,kt H m C n (Table 3 ). The abbreviation reflects the differences between the numbers of Im and HCl moieties in reactants ( i , j ) and products ( k , t , m , n ) on the both sides of the common expression. If HCl⋅Im forms a dimer then I ij,kt H m C d were n = 2 is replaced with the letter d . H 2 TPP, GdCl 3 and ClGdTPP are omitted because of they are constant reaction participants. The full compliance is presented in Table S1 in detail. Thermochemistry of ClGdTPP complexation with different numbers of Im moieties was analysed based on the calculations using all the tested combinations of functionals with basis sets. In order to avoid the local minima of the complicate gadolinium complexes, the several functionals and different basis sets were applied and sometime iteratively to provide similar trends for all the trials in their global minima. The results suspicious to local minima were iterated with the same functional and basis set applied to the compounds correctly optimized with the other settings. Diversity of functionals and bases sets let’s define better the settings to calculate Δ H , Δ G for ClGdTPP, ClGdTPP·kIm coordination compounds and side products from the initial reagents. MN15, M062X, M06HF, B3LYP, PBE0 were used with all the three basis sets and involving the empirical dispersion D3 whereas ωB97XD includes dispersion automatically. Table 3 Enthalpy and Gibbs free energies (in kJ/mol) of complexes formation from H 2 TPP, GdCl 3 ⋅2Im or GdCl 3 ⋅3Im and different numbers of Im ligands at T = 535 K. Reaction* M06HFD dTP M062X dTP M062XD xQc M062XD dTP ωB97XD xQc B3LYPD xQc ΔH ΔG ΔH ΔG ΔH ΔG ΔH ΔG ΔH ΔG ΔH ΔG I 20,20 H 2 C 0 −10 −28 31 5 21 −7 19 −6 10 −7 128 100 I 22,20 H 0 C d −256 −49 −176 20 −187 7 −190 5 −205 −1 −57 137 I 21,20 H 1 C 1 −65 −17 −16 20 −25 9 −27 9 −38 4 82 114 I 20,11 H 2 C 1 61 14 139 19 140 21 134 14 122 11 179 66 I 22,20 H 0 C 2 −121 −7 −62 35 −72 24 −75 23 −87 15 35 127 I 31,20 H 0 C d −141 −6 −79 41 −87 31 −91 30 −110 18 4 119 I 20,10 H 1 C 1 117 4 93 34 94 36 87 29 73 22 133 79 I 30,20 H 1 C 1 50 27 81 42 75 33 72 33 56 23 142 96 I 20,00 H 0 C d −3 19 39 61 48 69 37 58 17 41 50 81 I 30,10 H 0 C d −15 26 29 56 32 59 25 51 2 36 55 84 I 31,20 H 0 C 2 −6 37 35 57 28 48 25 48 7 34 96 109 I 30,01 H 0 C d 112 63 135 82 148 94 137 83 112 60 110 63 I 20,00 H 0 C 2 133 62 153 76 163 86 152 76 135 56 141 71 I 30,10 H 0 C 2 121 68 143 71 148 76 140 69 119 52 147 74 I 30,01 H 0 C 2 248 106 249 98 263 111 252 101 230 75 203 53 *H 2 TPP + GdCl 3 ⋅ i Im + j Im = ClGdTPP⋅ k Im + t Im + m HCl + n HCl⋅Im reactions are abbreviated as I ij,kt H m C n The main criterion of choosing appropriate functionals and basis sets is a negative or acceptable relatively small positive Δ G of the final complex and side products formation. The reactions were calculated in a vacuum instead of Im molten solvent that could ignore potential errors of the model losing Van der Waals (VdW) interactions (10–20 kJ/mol per each bond) and energy of hydrogen bonds (4–40 kJ/mol). The simplest final complex is bare ClGdTPP and it can be obtained with different combinations of side products: two imidazole hydrochloride (Im⋅HCl) molecules (reaction I 20,00 H 0 C 2 ), their dimer (reaction I 20,00 H 0 C d ) or unbound HCl and Im (reaction I 20,02 H 2 C 0 ) as shown in Fig. 2 . The reaction finishing with the dimer demonstrates the lower Δ G than the reaction resulting in two monomeric Im⋅HCl molecules but both are not preferable because of the positive heat changes: Δ H = −3 kJ/mol with Δ G > + 19 kJ/mol using the M06HFD&dTP overestimation through Δ H = + 50 kJ/mol and Δ G = + 81 kJ/mol with B3LYPD&xQc underestimation. The coordination compound of ClGdTPP with Im moieties requires different numbers of Im for initial reactants, final products and side products. The reaction I 20,20 H 2 C 0 between H 2 TPP and GdCl 3 ⋅2Im with final 7-coordinated ClGdTPP⋅2Im and two evolved HCl molecules is the most preferable according to exergonic process with Δ G = −7, −7, −6 kJ/mol with a slight “antientropic hindrance” due to endothermic heat changes Δ H = + 10, + 21, +19 kJ/mol obtained with ωB97XD&xQc, M062XD&xQc and M062XD&dTP, respectively. The B3LYPD&xQc underestimated Δ G = 100 kJ/mol and rarely used M06HFD&dTP overestimated Δ G = −28 kJ/mol. Such antientropic hindrances are observed for the cases when a number of reactants less than a number of products probably because of the model error, in which some interactions are not included. The reaction I 22,20 H 0 C d is exergonic with Δ G = −1 kJ/mol in ωB97XD&xQc, endergonic with very slight entropic hindrance and Δ G = + 5 kJ/mol in M062XD&dTP and Δ G = + 7 kJ/mol in M062XD&xQc but spontaneous reaction because of strong negative heat change Δ H = −205, −190, −187 kJ/mol for the exothermic reaction. The five most effective reactions according to the Gibbs free energies less than + 20 kJ/mol involve GdCl 3 ⋅2Im rather than GdCl 3 ⋅3Im (Table 3 ) although higher coordination number 6 intuitively is more complete rather than 5-coordinated complexes. GdCl 3 ⋅3Im → GdCl 3 ⋅2Im & Im decomposition is endothermic reaction, where Δ H = + 87 kJ/mol but slightly endergonic Δ G = + 13 kJ/mol is comparable with the Van der Waals interaction energy. Although most crystallographic data indicate six as a minimum coordination number for Gd and TPP-based compounds, short-lived intermediate GdCl 3 ⋅ i Im may be less coordinated during nonequilibrium reactions from the GdCl 3 crystal in molten Im to the final ClGdTPP⋅ k Im. The small Δ G values may say about potential reversible chemical reaction but this is practically impossible at high concentrations of Im. The first eight reactions from Table 3 could be assumed more or less effective due to low positive free energy in framework of the model errors where Δ G max = + 23, + 33, +33 kJ/mol in ωB97XD&xQc, M062XD&xQc and M062XD&dTP, respectively. However, only four reactions I 22,20 H 0 C d , I 21,20 H 1 C 1 , I 22,20 H 0 C 2 , I 31,20 H 0 C d can be considered as spontaneous or slightly entropic hindered processes with Δ G =[−1, + 30] kJ/mol due to the significant negative heat changes Δ H = [−25, −205] kJ/mol calculated using ωB97XD&xQc, M062XD&xQc and M062XD&dTP. It should be noted that the most preferable reaction H 2 TPP + GdCl 3 ·2Im = ClGdTPP·2Im + HCl + HCl (I 20,20 H 2 C 0 ) in the best computational settings is exergonic process between −7.38 kJ/mol and −6.25 kJ/mol at T = 535 K in molten imidazole but it become slightly endergonic at the room temperature though with a low barrier between + 0.02 kJ/mol and + 4.33 kJ/mol in ωB97XD&xQc and M062XD&dTP, respectively. Thus, ωB97XD&xQc, M062XD&xQc and M062XD&dTP are the most appropriate settings to calculate ClGdTPP coordinated with ligands. The dTP with ECP is the most computationally cost effective, i.e. optimal in the quality and convergence as well as time saving resource in contrast with large all-electron xQc especially in combination with ωB97XD that makes ωB97XD&xQc extremely time-consuming calculation. M062X&dTP without dispersion slightly and B3LYPD significantly underestimate Δ G reactions whereas M06HFD&dTP overestimates Δ G of the process. The other tested settings (see in SI) are inacceptable at all due to many unreasonable values. Electronic structures of ClGdTPP·kIm Electronic structures of ClGdTPP· k Im ( k = 0−2) were optimized with M062X&xQc, M062X&dTP and B3LYP&xQc for consideration. B3LYP&xQc produced the frontier β-UMO (lowest in energy unoccupied MO) formed almost absolutely by f-AO (Figure S1 ) that looks wrong because it should be π-MO according to the luminescence activity of the porphyrin compounds and computational researches using the other methods. M062X&dTP, using the ECP average in the basis set, can’t reproduce correctly all f-MOs for energetic schemes because this average over many deep AOs somehow involves and interacts with f -types, resulting in unclear f -MOs block and instead providing many mixed states, but this setting works well for the calculation of other properties, total energies and thermochemical reactions. The ClGdTPP·Im energy levels and numbering of MOs through dominantly Im localized and including all f -types as well as their linear combinations of AOs calculated using M062X&xQc is analysed on Fig. 3 . Frontier π-MOs are noted as ket-vectors |0〉 = HOMO, |0′〉 = LUMO and following MOs are numbered as | j 〉 α,β and | j ′〉 α,β , respectively, but spin subscription is omitted if MOs are the same type for both spins and close energy levels. More than two dozens of | j ≥0〉 α,β and | j ′≥0〉 α,β are π-types delocalized over porphyrin plane or on almost perpendicular to the terminate benzene rings and hardly mixed between the main and side cycles. M062X&xQc provided some mixtures between f -AOs and other AOs in linear combinations that led to 7 vacant MOs |19′〉 β −|25′〉 β with dominant, more than 66%, f -AOs contribution and significant, about 30%, f -AOs participation in 2 combinations of |18′〉 β , |26′〉 β with p,d AO vs 7 singly occupied MOs 96% strongly formed from f -AOs but 88% with 1 slight p,s-AOs admixture |99〉 α −|105〉 α and |98〉 α with only 22% f -AO participation. The unoccupied f -block is energetically laying much higher than many π-MO levels and even states based on d-AOs. Coordination Gd-Im bond is short enough (2.58Å) to admix Gd d-AO with π-MOs of the moiety and the terminal benzene motives but not with perpendicular tetra-pyrrole plane. The |14′〉 α MO localized almost exclusively on Im (92%) with insignificant benzene π-MO and gadolinium d-AO contributions. The |14′〉 β MO is the almost the same type but 79% Im participation with 11% d-AO contribution and a much less benzene π-MO admixture. d-AOs also notably contributes to unoccupied |9′〉 β 11% and maximum 22% to the similar |12′〉 β with Im-MO dominant such as for occupied |9〉 β and |12〉 β with nearly 6% both Gd and Cl d-AOs contributions. The |3′〉 α and |7′〉 α are significantly (81% and 39%) based on d-AO while there is no MO with dominantly localized on d-AO, instead it contributes to the nearest MOs in combination with f -AOs and Im MOs. ClGdTPP is more symmetrical (C 4 ) than ClGdTPP·Im (C 1 ) that provides degenerated states, in particular, several f -MOs (Figure S2). One of f -MOs splits and mixes with nearest and p and d (AO) orbitals, creating 6 pure f -MOs and 2 MOs with significant participation of f -AO. ClGdTPP·2Im (C 1 ) provides the more complicate electronic structure which is richer than ClGdTPP·Im due to a higher number of Im moieties but it does not play a critical role in the order of the structure though more states with Im contributions are encountered because of stronger interaction with the main structure. Conclusions Electronic structure and high multiplicities of ClGdTPP were calculated using the M062X and B3LYP functionals with the def2-SVP/def2-TZVP[Cl]/def2-TZVPP[Gd] and relativistic all-electron x2c-SVPall-2c/x2c-SVP-all[H]/x2c-TZVPall[Cl]/x2c-QZVPall-2c[Gd] basis sets to define energy levels and electron density shapes of the molecular orbitals which are the frontiers with the several nearest ones and the f- type as well as localized on ligands. Minnesota functionals family, ωB97XD, B3LYP and PBE0 with the same and SDDall basis sets were applied for the thermochemical analysis of ClGdTPP formation from GdCl 3 and H 2 TPP in molten imidazole. Enthalpies and Gibbs free energies of all possible coordination compounds of ClGdTPP with imidazole ligands (up to 2) and side products were compared. ClGdTPP⋅2Im was found as the most energetically preferable complex formed in the reaction between H 2 TPP and GdCl 3 ⋅2Im in present of different numbers of extra free imidazole molecules. The ωB97XD&xQc, M062XD&xQc and M062XD&dTP functionals with the def2-SVP/def2-TZVP[Cl]/def2-TZVPP[Gd] and better x2c-SVPall-2c/x2c-SVP-all[H]/x2c-TZVPall[Cl]/x2c-QZVPall-2c[Gd] basis sets were defined as the most appropriate settings to calculate the electronic structures and thermochemical formations of ClGd-porphyrin family with ligands. Declarations Author Contribution V.P. conceptualized idea, obtained dates, wrote main text, prepared tables and figures.E.S. managed the project, wrote introduction, considered the main text, created figure 2.D.L. consulted on experimental data, discussed tables, figures. 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Fuchs, T.M.; Gleditzsch, M.; Schäfer, R. Local Coordination Numbers of up to 19 in Gadolinium–Tin Alloy Nanoclusters. The Journal of Chemical Physics 2020, 153 , 164308, doi: 10.1063/5.0027772 . Additional Declarations No competing interests reported. Supplementary Files GdTPPform030725si.doc Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7155766","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":506009642,"identity":"89508063-4da1-4d8c-96cf-5d2233b5e01f","order_by":0,"name":"Vladimir A. Pomogaev","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2ElEQVRIiWNgGAWjYFAC5oYDIIofRPAQp4URokWygRQtYMrgALFaDI4fbDzwcccdOeMbyc8evKk4zGA+I4GAljOJDQdnnnlmbHYjzdxwzpk0BpkbBLRINiQ2HOZtO5y47UaCmTRvmw2DhAQhLf0PGw7/BWrZPCP9mzTvPwnCWvglgLYwArVskMgB2tJAhC38Eg8bDva2PTOWOPOmTHLOsTQeCZ4H+LWw8Scf/vCz7Y4cf3v6Nok3NYflJNgJ2AIFBxgYBCAqiYxNsBb+A8QqHgWjYBSMgpEGAB3wSH9udB3sAAAAAElFTkSuQmCC","orcid":"","institution":"Saint-Petersburg State University","correspondingAuthor":true,"prefix":"","firstName":"Vladimir","middleName":"A.","lastName":"Pomogaev","suffix":""},{"id":506009643,"identity":"d05451af-0eff-4804-b5fa-0ec78c2db9e7","order_by":1,"name":"Daniil A. 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Solovyeva","email":"","orcid":"","institution":"Saint-Petersburg State University","correspondingAuthor":false,"prefix":"","firstName":"Elena","middleName":"V.","lastName":"Solovyeva","suffix":""}],"badges":[],"createdAt":"2025-07-18 08:53:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7155766/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7155766/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":90347632,"identity":"31a83cea-3a01-49ce-a0c9-6aa07ae50242","added_by":"auto","created_at":"2025-09-01 16:38:36","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":95760,"visible":true,"origin":"","legend":"\u003cp\u003eGdCl\u003csub\u003e3 \u003c/sub\u003e(3´3´3) unpacking supercell following by the coordination with Im molecules.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7155766/v1/0cd03a1c83e770bb59cdfecc.png"},{"id":90347855,"identity":"59be0188-b758-4ee4-857e-5d248d629b00","added_by":"auto","created_at":"2025-09-01 16:46:37","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":789797,"visible":true,"origin":"","legend":"\u003cp\u003ePossible ways of Gd coordination with Cl, H\u003csub\u003e2\u003c/sub\u003eTPP and \u003cem\u003ek\u003c/em\u003eIm (\u003cem\u003ek\u003c/em\u003e=0-2) as well as HCl, Im and ImHCl side products produced from the initial reactants.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-7155766/v1/daacca6c6138200029317c84.png"},{"id":90347637,"identity":"0f979d0a-d6bb-4b46-bdd9-25b529157e53","added_by":"auto","created_at":"2025-09-01 16:38:37","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":1848492,"visible":true,"origin":"","legend":"\u003cp\u003eScheme and numbering of MOs with the vacant (green and dark green) vs singly occupied \u003cem\u003ef\u003c/em\u003e-MOs (blue and light blue) through MOs based on d-AO (violet) up to Im dominantly contributed states (red and light brown). The frontier p-MOs and the remaining MOs are black and grey lines, respectively.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-7155766/v1/6d30f1b6ed60757ab64e7ad1.png"},{"id":92001322,"identity":"19091aaf-1205-4ec9-84cd-a9bf7bfd83d6","added_by":"auto","created_at":"2025-09-23 14:32:08","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4231836,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7155766/v1/78f140bc-a440-4f14-aa1a-30998917773a.pdf"},{"id":90347854,"identity":"67f640db-99f6-45a4-82e5-3ad9a01be704","added_by":"auto","created_at":"2025-09-01 16:46:37","extension":"doc","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":1373696,"visible":true,"origin":"","legend":"","description":"","filename":"GdTPPform030725si.doc","url":"https://assets-eu.researchsquare.com/files/rs-7155766/v1/cd8daf9ab0516122059378e6.doc"}],"financialInterests":"No competing interests reported.","formattedTitle":"Thermochemical transformations of gadolinium chloride and tetraphenylporphyrin into coordination complexes with imidazole ligands","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCoordinated metalloporphyrins with lanthanides have long attracted undiminished research activity due to their unique photoinduced chemical and optical properties, which might be applied in various fields of science, medicine and technology. Among the lanthanides, gadolinium is capable of providing the widest range of beneficial properties for medical applications of metalloporphyrins. Its long electron-spin relaxation time, arising due a high number of unpaired electrons opens up the possibility for the use of Gd porphyrins in magnetic resonance imaging especially as necrosis-avid contrast agents [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Large thermal neutron cross section of \u003csup\u003e157\u003c/sup\u003eGd isotope, which a natural abundance is about 15.7%, provides a high potential of Gd porphyrins for neutron capture therapy [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Enhanced phosphorescence of porphyrin complexes with Gd can be utilized for oxygen sensing [\u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Altogether, a variety of useful Gd porphyrins properties makes them as promising theranostic agents [\u003cspan additionalcitationids=\"CR9\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eCoordination of the lanthanides with tetrapyrrole cavity does not proceed easily due to their large radius. Two capable methods for the synthesis of Gd porphyrins are heating of the free base porphyrin with gadolinium acetylacetonate (Gd(acac)\u003csub\u003e3\u003c/sub\u003e) in inert solvent [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e] or with gadolinium chloride (GdCl\u003csub\u003e3\u003c/sub\u003e) in molten imidazole [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. First method affords the Gd porphyrins with acetylacetonate ligand, which is relatively stable towards the ligand exchange and exists in the monomeric form [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e], which allows to confirming its structure unambiguously by X-ray diffraction (XRD) [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. In contrast, the reaction of porphyrins with GdCl\u003csub\u003e3\u003c/sub\u003e in molten imidazole, which serve in the reaction as both solvent and base, initially affords the product with axial -Cl ligand [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], which is quite labile and can be substituted by the -OH group at the treatment of the reaction mixture with water [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Such complexes can associate in the bridged multinuclear structures [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], which might be the reason why the researchers are unable to grow a crystal suitable for the XRD structure determination. Owing to the structural uncertainty of these complexes, many authors depict their structures without an odd number of charged ligands [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e] or without ligand at all [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Nevertheless, formation of five-coordinated Gd porphyrins with a single monodentate axial ligand such as Cl or OH is highly unlikely without additional ligands, since the lanthanides tend to form complexes with coordination numbers no less than 6 [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. This leads us to assume that imidazole (Im) also acts as an ligand which saturates the coordination sphere of Gd during the complexation with porphyrin, but can leave the complex easily upon an influence of other ligands such as solvents used for the workup. This assumption is supported by the observed phenomenon of reversible Im coordination to the Gd porphyrin in methanol [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e] or Im-HCl buffer [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Moreover, coordination of Im on Gd protects the triplet excited state of the complex, dramatically increasing its phosphorescence quantum yield [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. At the same time, the nature of the coordination ligands is often unclear, which impedes the correct interpretation of experimental results.\u003c/p\u003e\u003cp\u003eOn the whole, the obscurity must not remain for such a promising family of metalloporphyrins obtaining through the widely used synthetic protocol. In the absence of direct experimental data, quantum chemical calculations become the only tool that can shed light on the reaction between GdCl\u003csub\u003e3\u003c/sub\u003e and free base porphyrins in molten imidazole. This study aims to elucidate the Im role in the reaction of GdCl\u003csub\u003e3\u003c/sub\u003e with \u003cem\u003emeso\u003c/em\u003e-tetraphenylporphyrin (H\u003csub\u003e2\u003c/sub\u003eTPP) and the structure of the coordination product by DFT calculations of thermochemical parameters of complexation with various numbers of Im ligands in typical reaction conditions of boiling imidazole.\u003c/p\u003e\u003cp\u003eThe work presents various pathways for thermochemical transformations of gadolinium chloride and tetraphenylporphyrin in molten imidazole into coordination complexes based on quantum-mechanical calculations of vibrational modes and corresponding free energies at the reaction temperature at T\u0026thinsp;=\u0026thinsp;535K to elucidate mechanism of such conversions when we know only initial reactants and main final products. Energetical preferable reactions were selected among all possible processes involving gadolinium chloride, tetraphenylporphyrin and imidazole at the corresponding conditions. Structural optimization was performed at high spin multiplicity of gadolinium corresponding to the minimum total energy and the scheme of molecular orbital energies are considered including blocks of those almost exclusively formed from \u003cem\u003ef\u003c/em\u003e atomic orbitales.\u003c/p\u003e"},{"header":"Computational methods","content":"\u003cp\u003eOptimization and properties calculation of initial reagents (H\u003csub\u003e2\u003c/sub\u003eTPP, Im, GdCl\u003csub\u003e3\u003c/sub\u003e), final compounds (ClGdTPP\u0026middot;\u003cem\u003ek\u003c/em\u003eIm with different numbers of Im moieties, \u003cem\u003ek\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0\u0026ndash;2 and side products were performed in the framework of DFT theory. Various functionals and basis sets, the most relevant to the energy-efficient thermochemical reactions of ClGdTPP complexation accompanied by Im moieties coordination were considered. In particular, the following functionals and basis sets were applied for the computational investigation: i) hybrid B3LYP popular for porphyrins study [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]; ii) MN15, M062X and M06HF functionals family of Truhlar\u0026rsquo;s group from Minnesota University [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]; iii) ωB97XD including both long-range correction and empirical Grimme's D2 dispersion model from Head-Gordon and co-workers [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]; and iv) PBE0 Perdew, Burke and Ernzerhof hybrid functional for diversity [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Empirical dispersion D3 was applied for all the functionals excluding ωB97XD for the optimization and calculation of complexation energies because it deals with thermochemistry of the macrocyclic aromatic complexes which include heavy elements [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe basis sets choice is restricted by available effective basis functions developed for gadolinium. The following basis sets were tested for various ClGdTPP multiplicities and applied for thermochemical reactions: the hybrid diffused polarization-consistent def2-SVP/def2-TZVP[Cl]/def2-TZVPP-ECP[Gd] (noted as dTP) basis sets of the Karlsruhe group [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e], Stuttgart potentials SDDall [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] vs the last decade developed largest relativistic all-electron hybrid ahlrichs_x2c basis sets family (xQc abbreviation) consisting of x2c-QZVPall-2c for Gd, x2c-TZVPall for Cl, x2c-SVP-all for H and x2c-SVPall-2c for the rest elements [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] which is downloaded from the Basis Set Exchange homepage [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe Gaussian 16 quantum-chemical (QM) package [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e] was used for all calculations. Construction and visualisation of the structures under interest were performed using Gaussview 6 and Chemcraft [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e] sites. The calculations were carried out in Gaussian 16 and optimizations reached all real vibrational frequencies. The calculations of molecular electrostatic potentials and MO delocalization index with \u003cem\u003ef\u003c/em\u003e-AO participation percentages were obtained in the framework Multiwfn package [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cp\u003e\u003cem\u003eClGdTPP structure and multiplicity\u003c/em\u003e\u003c/p\u003e\u003cp\u003eThe neutral ClGdTPP complex with various multiplicities was optimized using the Minnesota functionals family M062X, MN15 and MNHF as well as ωB97XD, B3LYP and PBE0 with SDD, dTP, xQc basis sets to verify the most appropriate spin multiplicity m\u0026thinsp;=\u0026thinsp;2S\u0026thinsp;+\u0026thinsp;1 for ClGdTPP minimum energies in comparison with other Gd containing compounds [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e] (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Gadolinium atom has 7 unpaired electrons on 4f shell which provides the highest multiplicity of ground electronic state with the minimum energy among the lanthanides and all metals in general. Thus, the unpaired \u003cem\u003ef\u003c/em\u003e-electrons should provide a group of singly occupied (SO) α molecular orbitals (MO) formed dominantly from \u003cem\u003ef\u003c/em\u003e-atomic orbitals (AO) and the corresponding unoccupied β counterparts of low-laying MO energies. Molecular motives consisting of Gd and Cl exclusively define the multiplicity of ClGdTPP and GdCl\u003csub\u003e3\u003c/sub\u003e complexes and their coordination compounds.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eDifference in minimum energies of ClGdTPP and GdCl\u003csub\u003e3\u003c/sub\u003e structures optimized with various multiplicities in respect to the structure with m\u0026thinsp;=\u0026thinsp;8 (\u003cem\u003eE\u003c/em\u003e\u003csub\u003em\u003c/sub\u003e\u0026minus;\u003cem\u003eE\u003c/em\u003e\u003csub\u003em=8\u003c/sub\u003e, eV).\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e\u003cp\u003eMultiplicity\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMN15 \u0026amp; xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.58\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eM062X \u0026amp; xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7.94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.83\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eωB97XD \u0026amp; xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.43\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eωB97XD \u0026amp; SDD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.37\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYP \u0026amp; SDD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.57\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYP \u0026amp; dTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6.90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.60\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYP \u0026amp; xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e5.79\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1.59\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGdCl\u003csub\u003e3\u003c/sub\u003e@M062X\u0026amp;dTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.57\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGdCl\u003csub\u003e3\u003c/sub\u003e@M062X\u0026amp;xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.74\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e3.84\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGdCl\u003csub\u003e3\u003c/sub\u003e@ωB97XD\u0026amp;xQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e4.33\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAll the methods provide the total minimum energy for m\u0026thinsp;=\u0026thinsp;8. The other possible multiples corresponding to the electroneutral compounds have the higher energies. The obtained energy gaps vary greatly between the applied methods and basis sets especially. The closest to the minima is m\u0026thinsp;=\u0026thinsp;10 for ClGdTPP with energy differences not larger than ~\u0026thinsp;2 eV whereas GdCl\u003csub\u003e3\u003c/sub\u003e gives\u0026thinsp;~\u0026thinsp;4 eV. The complexes calculated using the large relativistic all-electron xQc for m\u0026thinsp;=\u0026thinsp;6 have similar energy difference whereas the other smaller basis sets with ECP provide notably higher values, which are closer to m\u0026thinsp;=\u0026thinsp;4 and m\u0026thinsp;=\u0026thinsp;2.\u003c/p\u003e\u003cp\u003eThe same settings of functionals with basis sets were involved to evaluate structural features of the optimized neutral ClGdTPP complex with multiplicity equal to 8. |Gd\u0026minus;Cl| and |Gd\u0026minus;N| bond lengths, angles between these atoms and non-planarity height h\u003csub\u003eGd\u003c/sub\u003e were calculated and compared (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The large ionic radius provides Gd atom to be placed out of the N\u003csub\u003e4\u003c/sub\u003e square plane [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e] and Cl is axially coordinated with the metal atom. The distance between two opposite N atoms and their angle with Gd \u0026ang;NGdN reflects a degree of non-planarity h\u003csub\u003eGd\u003c/sub\u003e assumed as the N\u0026minus;Gd length projection on the Gd\u0026minus;Cl axis that is a height from Gd to the plane defined as h\u003csub\u003eGd\u003c/sub\u003e=0.5|Gd\u0026minus;N|\u0026sdot;cos(\u0026ang;NGdN).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSelected distances (\u0026Aring;) and planar angles (\u003cem\u003e\u0026deg;\u003c/em\u003e) in ClGdTPP structure (m\u0026thinsp;=\u0026thinsp;8) optimized in different methods and bases.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003efunctional\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ebasis\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026ang;NGdCl\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eGd\u0026minus;Cl\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eGd\u0026minus;N\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026ang;NGdN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eh\u003csub\u003eGd\u003c/sub\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMN15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e117.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.560\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.348\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e125.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.176\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eM062XD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.561\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.331\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e127.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.139\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eM06HFD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.553\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.317\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e127.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.121\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePBE0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.544\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.323\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e127.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.114\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e117.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.597\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.365\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e125.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.197\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.571\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.346\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e126.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.054\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eB3LYPD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.564\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.347\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e126.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.156\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCAM-B3LYPD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.555\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.325\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e127.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.134\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eωB97XD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e117.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.581\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.357\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e124.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.098\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eωB97XD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSDD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e116.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e2.603\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.334\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e126.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e1.051\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe bond length Gd\u0026minus;N\u0026thinsp;=\u0026thinsp;2.32 \u0026Aring; measured for GdTPP coordination compound with acetylacetone as an axial ligand [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e] better coincides with 2.317 \u0026Aring; and 2.323 \u0026Aring; distances calculated with M06HFD\u0026amp;dTP and PBE0\u0026amp;dTP, respectively. The only evaluated non-planarity h\u003csub\u003eGd\u003c/sub\u003e=1.31 \u0026Aring; is closer to 1.197 \u0026Aring; calculated in B3LYP\u0026amp;xQc but Gd\u0026minus;N\u0026thinsp;=\u0026thinsp;2.427\u0026ndash;2.445\u0026Aring; [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e] or Gd\u0026minus;N\u0026thinsp;=\u0026thinsp;2.401\u0026ndash;2.428 \u0026Aring; [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e] is little bit higher than the maximum bond length 2.365 \u0026Aring; obtained using the same settings. Nevertheless, the other combinations of functionals with basis sets provide also adequate results reasonably corresponding to the experimental data taking into account the errors of measurements and calculations. The Gd out-of-plane height is not less than 1.05 \u0026Aring; which is defined by \u0026ang;NGdN between 125\u0026deg;\u0026amp;128\u0026deg; and |Gd\u0026minus;N| in the range of 2.32\u0026divide;2.36 \u0026Aring;. The coordination bond length between Cl and Gd varies from 2.54 \u0026Aring; to 2.6 \u0026Aring;. Despite the structural parameters calculated in some settings are closer to the know experimental data, reasonable thermodynamics of complexation from initial reagents to final products as well as correct experimental spectral data reproduction are also should be provided that cannot be reached using the same functional and basis sets. Thermochemical process of ClGdTPP formation requires adequate settings to calculate the correct differences of enthalpies and free Gibbs energies resulting in the reaction.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eClGdTPP is synthesized from H\u003csub\u003e2\u003c/sub\u003eTPP and GdCl\u003csub\u003e3\u003c/sub\u003e crystalline starting materials dissolved in anhydrous molten Im at \u003cem\u003eT\u003c/em\u003e\u0026thinsp;=\u0026thinsp;535 K where an expected reaction proceeds through the coordination of GdCl\u003csub\u003e3\u003c/sub\u003e with several imidazole molecules which then attack H\u003csub\u003e2\u003c/sub\u003eTPP. The GdCl\u003csub\u003e3\u003c/sub\u003e crystal (space group 176, P63/m) suffers destroying and mixing with other reagents under the high temperature (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). At the first process of GdCl\u003csub\u003e3\u003c/sub\u003e crystal dissolving, GdCl\u003csub\u003e3\u003c/sub\u003e\u003cb\u003e\u0026middot;\u003c/b\u003e2Im and GdCl\u003csub\u003e3\u003c/sub\u003e\u003cb\u003e\u0026middot;\u003c/b\u003e3Im compounds are formed most probably. The supercell (3\u0026times;3\u0026times;3) unpacking leads to the structure with 6 equal bonds |Gd\u0026minus;Cl|=2.82 \u0026Aring; and the crystalline bonds can be broken in two ways, resulting in different GdCl\u003csub\u003e3\u003c/sub\u003e structures, but both free complexes are optimized in the trigonal planar D\u003csub\u003e3h\u003c/sub\u003e compound, which can attract several Im ligands from the environment (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThe Gd complexes are able to coordinate with many ligands, particularly, imidazole moieties that depends on the ligand size, orientation and attachment site, steric and electronic properties. ClGdTPP has five bonds with four nitrogen atoms and one chloride anion and can rearrange into compounds with 6 and higher coordination numbers, through 10 [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e] or even up to 19 as in nanoclusters with GdSn [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e]. This allows predicting ClGdTPP coordination with several Im molecules. GdCl\u003csub\u003e3\u003c/sub\u003e\u003cb\u003e\u0026middot;\u003c/b\u003e2Im and GdCl\u003csub\u003e3\u003c/sub\u003e\u003cb\u003e\u0026middot;\u003c/b\u003e3Im are considered because they are the simplest precursors required for the ClGdTPP formation.\u003c/p\u003e\u003cp\u003e\u003cem\u003eThermochemistry of ClGdTPP\u0026middot;kIm formation\u003c/em\u003e\u003c/p\u003e\u003cp\u003eThermochemical analysis of H\u003csub\u003e2\u003c/sub\u003eTPP, GdCl\u003csub\u003e3\u003c/sub\u003e and Im interaction requires a total optimization verified by all real frequencies that allows calculating the difference between standard enthalpies (Δ\u003cem\u003eH\u0026thinsp;=\u003c/em\u003e\u0026thinsp;Δ\u003cem\u003eH\u003c/em\u003e\u0026deg;\u003csub\u003e535\u003c/sub\u003e) and standard Gibbs free energies (Δ\u003cem\u003eG\u0026thinsp;=\u003c/em\u003e\u0026thinsp;Δ\u003cem\u003eG\u003c/em\u003e\u0026deg;\u003csub\u003e535\u003c/sub\u003e) at \u003cem\u003eT\u003c/em\u003e\u0026thinsp;=\u0026thinsp;535 K (the experimental synthesis temperature is 262\u0026deg;C) of reactants and final products. Since only initial reactants and reaction conditions are documented for the experimental procedure of ClGdTPP synthesis but intermediate species are inaccessible, the initial components and final products were considered to model the most energetically profitable reaction pathway and to interpret the obtained results in correspondence with the known experimental data.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThere is no published data on how many Im molecules can be attached to ClGdTPP and on the exact structure of this coordination compound. Possible ClGdTPP\u0026middot;\u003cem\u003ek\u003c/em\u003eIm (\u003cem\u003ek\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0\u0026minus;2) formations from H\u003csub\u003e2\u003c/sub\u003eTPP and GdCl\u003csub\u003e3\u003c/sub\u003e\u003cb\u003e\u0026middot;\u003c/b\u003e\u003cem\u003ei\u003c/em\u003eIm (\u003cem\u003ei\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1\u0026minus;2) are compiled in the general scheme (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Final ClGdTPP\u0026middot;\u003cem\u003ek\u003c/em\u003eIm are accompanied with several numbers of side products such as single hydrochloride (HCl) and imidazole molecules or their associate. The common formula for all possible reactions with \u003cem\u003ei\u003c/em\u003e,\u003cem\u003ej\u003c/em\u003e,\u003cem\u003ek\u003c/em\u003e,\u003cem\u003et\u003c/em\u003e,\u003cem\u003em\u003c/em\u003e,\u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0\u0026minus;2 expressed as H\u003csub\u003e2\u003c/sub\u003eTPP\u0026thinsp;+\u0026thinsp;GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;\u003cem\u003ei\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003ej\u003c/em\u003eIm\u0026thinsp;=\u0026thinsp;ClGdTPP\u0026sdot;\u003cem\u003ek\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003et\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003em\u003c/em\u003eHCl\u0026thinsp;+\u0026thinsp;\u003cem\u003en\u003c/em\u003eHCl\u0026sdot;Im abbreviated through I\u003csub\u003e\u003cem\u003eij,kt\u003c/em\u003e\u003c/sub\u003eH\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003eC\u003csub\u003e\u003cem\u003en\u003c/em\u003e\u003c/sub\u003e (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The abbreviation reflects the differences between the numbers of Im and HCl moieties in reactants (\u003cem\u003ei\u003c/em\u003e,\u003cem\u003ej\u003c/em\u003e) and products (\u003cem\u003ek\u003c/em\u003e,\u003cem\u003et\u003c/em\u003e,\u003cem\u003em\u003c/em\u003e,\u003cem\u003en\u003c/em\u003e) on the both sides of the common expression. If HCl\u0026sdot;Im forms a dimer then I\u003csub\u003e\u003cem\u003eij,kt\u003c/em\u003e\u003c/sub\u003eH\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003eC\u003csub\u003e\u003cem\u003ed\u003c/em\u003e\u003c/sub\u003e were \u003cem\u003en\u003c/em\u003e\u0026thinsp;=\u0026thinsp;2 is replaced with the letter \u003cem\u003ed\u003c/em\u003e. H\u003csub\u003e2\u003c/sub\u003eTPP, GdCl\u003csub\u003e3\u003c/sub\u003e and ClGdTPP are omitted because of they are constant reaction participants. The full compliance is presented in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e in detail.\u003c/p\u003e\u003cp\u003eThermochemistry of ClGdTPP complexation with different numbers of Im moieties was analysed based on the calculations using all the tested combinations of functionals with basis sets. In order to avoid the local minima of the complicate gadolinium complexes, the several functionals and different basis sets were applied and sometime iteratively to provide similar trends for all the trials in their global minima. The results suspicious to local minima were iterated with the same functional and basis set applied to the compounds correctly optimized with the other settings. Diversity of functionals and bases sets let\u0026rsquo;s define better the settings to calculate Δ\u003cem\u003eH\u003c/em\u003e, Δ\u003cem\u003eG\u003c/em\u003e for ClGdTPP, ClGdTPP\u0026middot;kIm coordination compounds and side products from the initial reagents. MN15, M062X, M06HF, B3LYP, PBE0 were used with all the three basis sets and involving the empirical dispersion D3 whereas ωB97XD includes dispersion automatically.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eEnthalpy and Gibbs free energies (in kJ/mol) of complexes formation from H\u003csub\u003e2\u003c/sub\u003eTPP, GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;2Im or GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;3Im and different numbers of Im ligands at T\u0026thinsp;=\u0026thinsp;535 K.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"13\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eReaction*\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eM06HFD\u003c/p\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003eM062X\u003c/p\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003eM062XD\u003c/p\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e\u003cp\u003eM062XD\u003c/p\u003e\u003cp\u003edTP\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e\u003cp\u003eωB97XD\u003c/p\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e\u003cp\u003eB3LYPD\u003c/p\u003e\u003cp\u003exQc\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003eΔH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003eΔG\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e20,20\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eC\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e\u0026minus;7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e\u0026minus;6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e\u0026minus;7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e128\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e100\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e22,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;256\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026minus;176\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;187\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026minus;190\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e\u0026minus;205\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e\u0026minus;1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e\u0026minus;57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e137\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e21,20\u003c/sub\u003eH\u003csub\u003e1\u003c/sub\u003eC\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026minus;16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026minus;27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e\u0026minus;38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e114\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e20,11\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eC\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e61\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e139\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e140\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e21\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e134\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e122\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e179\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e66\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e22,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;121\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026minus;62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e24\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026minus;75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e\u0026minus;87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e127\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e31,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;141\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e\u0026minus;6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e\u0026minus;79\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e41\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u0026minus;87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026minus;91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e\u0026minus;110\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e119\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e20,10\u003c/sub\u003eH\u003csub\u003e1\u003c/sub\u003eC\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e117\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e133\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e79\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e30,20\u003c/sub\u003eH\u003csub\u003e1\u003c/sub\u003eC\u003csub\u003e1\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e72\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e142\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e96\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e20,00\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e61\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e41\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e81\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e30,10\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e59\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e84\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e31,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026minus;6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e35\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e57\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e109\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e30,01\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e112\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e135\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e148\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e94\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e137\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e112\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e110\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e63\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e20,00\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e133\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e153\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e163\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e152\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e135\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e56\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e141\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e71\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e30,10\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e121\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e68\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e143\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e148\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e140\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e69\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e119\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e52\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e147\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e74\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI\u003csub\u003e30,01\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e248\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e106\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e249\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e263\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e111\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e252\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e101\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e230\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003e75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e203\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c13\"\u003e\u003cp\u003e53\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"13\"\u003e*H\u003csub\u003e2\u003c/sub\u003eTPP\u0026thinsp;+\u0026thinsp;GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;\u003cem\u003ei\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003ej\u003c/em\u003eIm\u0026thinsp;=\u0026thinsp;ClGdTPP\u0026sdot;\u003cem\u003ek\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003et\u003c/em\u003eIm\u0026thinsp;+\u0026thinsp;\u003cem\u003em\u003c/em\u003eHCl\u0026thinsp;+\u0026thinsp;\u003cem\u003en\u003c/em\u003eHCl\u0026sdot;Im reactions are abbreviated as I\u003csub\u003e\u003cem\u003eij,kt\u003c/em\u003e\u003c/sub\u003eH\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003eC\u003csub\u003e\u003cem\u003en\u003c/em\u003e\u003c/sub\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe main criterion of choosing appropriate functionals and basis sets is a negative or acceptable relatively small positive Δ\u003cem\u003eG\u003c/em\u003e of the final complex and side products formation. The reactions were calculated in a vacuum instead of Im molten solvent that could ignore potential errors of the model losing Van der Waals (VdW) interactions (10\u0026ndash;20 kJ/mol per each bond) and energy of hydrogen bonds (4\u0026ndash;40 kJ/mol).\u003c/p\u003e\u003cp\u003eThe simplest final complex is bare ClGdTPP and it can be obtained with different combinations of side products: two imidazole hydrochloride (Im\u0026sdot;HCl) molecules (reaction I\u003csub\u003e20,00\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e), their dimer (reaction I\u003csub\u003e20,00\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e) or unbound HCl and Im (reaction I\u003csub\u003e20,02\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eC\u003csub\u003e0\u003c/sub\u003e) as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The reaction finishing with the dimer demonstrates the lower Δ\u003cem\u003eG\u003c/em\u003e than the reaction resulting in two monomeric Im\u0026sdot;HCl molecules but both are not preferable because of the positive heat changes: Δ\u003cem\u003eH\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;3 kJ/mol with Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;+\u0026thinsp;19 kJ/mol using the M06HFD\u0026amp;dTP overestimation through Δ\u003cem\u003eH\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;50 kJ/mol and Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;81 kJ/mol with B3LYPD\u0026amp;xQc underestimation.\u003c/p\u003e\u003cp\u003eThe coordination compound of ClGdTPP with Im moieties requires different numbers of Im for initial reactants, final products and side products. The reaction I\u003csub\u003e20,20\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eC\u003csub\u003e0\u003c/sub\u003e between H\u003csub\u003e2\u003c/sub\u003eTPP and GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;2Im with final 7-coordinated ClGdTPP\u0026sdot;2Im and two evolved HCl molecules is the most preferable according to exergonic process with Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;7, \u0026minus;7, \u0026minus;6 kJ/mol with a slight \u0026ldquo;antientropic hindrance\u0026rdquo; due to endothermic heat changes Δ\u003cem\u003eH\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;10, +\u0026thinsp;21, +19 kJ/mol obtained with ωB97XD\u0026amp;xQc, M062XD\u0026amp;xQc and M062XD\u0026amp;dTP, respectively. The B3LYPD\u0026amp;xQc underestimated Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;100 kJ/mol and rarely used M06HFD\u0026amp;dTP overestimated Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;28 kJ/mol. Such antientropic hindrances are observed for the cases when a number of reactants less than a number of products probably because of the model error, in which some interactions are not included. The reaction I\u003csub\u003e22,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e is exergonic with Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;1 kJ/mol in ωB97XD\u0026amp;xQc, endergonic with very slight entropic hindrance and Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;5 kJ/mol in M062XD\u0026amp;dTP and Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;7 kJ/mol in M062XD\u0026amp;xQc but spontaneous reaction because of strong negative heat change Δ\u003cem\u003eH\u003c/em\u003e\u0026thinsp;=\u0026thinsp;\u0026minus;205, \u0026minus;190, \u0026minus;187 kJ/mol for the exothermic reaction.\u003c/p\u003e\u003cp\u003eThe five most effective reactions according to the Gibbs free energies less than +\u0026thinsp;20 kJ/mol involve GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;2Im rather than GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;3Im (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) although higher coordination number 6 intuitively is more complete rather than 5-coordinated complexes. GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;3Im \u0026rarr; GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;2Im \u0026amp; Im decomposition is endothermic reaction, where Δ\u003cem\u003eH\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;87 kJ/mol but slightly endergonic Δ\u003cem\u003eG\u003c/em\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;13 kJ/mol is comparable with the Van der Waals interaction energy. Although most crystallographic data indicate six as a minimum coordination number for Gd and TPP-based compounds, short-lived intermediate GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;\u003cem\u003ei\u003c/em\u003eIm may be less coordinated during nonequilibrium reactions from the GdCl\u003csub\u003e3\u003c/sub\u003e crystal in molten Im to the final ClGdTPP\u0026sdot;\u003cem\u003ek\u003c/em\u003eIm. The small Δ\u003cem\u003eG\u003c/em\u003e values may say about potential reversible chemical reaction but this is practically impossible at high concentrations of Im.\u003c/p\u003e\u003cp\u003eThe first eight reactions from Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e could be assumed more or less effective due to low positive free energy in framework of the model errors where Δ\u003cem\u003eG\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;+\u0026thinsp;23, +\u0026thinsp;33, +33 kJ/mol in ωB97XD\u0026amp;xQc, M062XD\u0026amp;xQc and M062XD\u0026amp;dTP, respectively. However, only four reactions I\u003csub\u003e22,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e, I\u003csub\u003e21,20\u003c/sub\u003eH\u003csub\u003e1\u003c/sub\u003eC\u003csub\u003e1\u003c/sub\u003e, I\u003csub\u003e22,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e, I\u003csub\u003e31,20\u003c/sub\u003eH\u003csub\u003e0\u003c/sub\u003eC\u003csub\u003ed\u003c/sub\u003e can be considered as spontaneous or slightly entropic hindered processes with Δ\u003cem\u003eG\u003c/em\u003e =[\u0026minus;1, +\u0026thinsp;30] kJ/mol due to the significant negative heat changes Δ\u003cem\u003eH\u003c/em\u003e = [\u0026minus;25, \u0026minus;205] kJ/mol calculated using ωB97XD\u0026amp;xQc, M062XD\u0026amp;xQc and M062XD\u0026amp;dTP. It should be noted that the most preferable reaction H\u003csub\u003e2\u003c/sub\u003eTPP\u0026thinsp;+\u0026thinsp;GdCl\u003csub\u003e3\u003c/sub\u003e\u0026middot;2Im\u0026thinsp;=\u0026thinsp;ClGdTPP\u0026middot;2Im\u0026thinsp;+\u0026thinsp;HCl\u0026thinsp;+\u0026thinsp;HCl (I\u003csub\u003e20,20\u003c/sub\u003eH\u003csub\u003e2\u003c/sub\u003eC\u003csub\u003e0\u003c/sub\u003e) in the best computational settings is exergonic process between \u0026minus;7.38 kJ/mol and \u0026minus;6.25 kJ/mol at T\u0026thinsp;=\u0026thinsp;535 K in molten imidazole but it become slightly endergonic at the room temperature though with a low barrier between +\u0026thinsp;0.02 kJ/mol and +\u0026thinsp;4.33 kJ/mol in ωB97XD\u0026amp;xQc and M062XD\u0026amp;dTP, respectively.\u003c/p\u003e\u003cp\u003eThus, ωB97XD\u0026amp;xQc, M062XD\u0026amp;xQc and M062XD\u0026amp;dTP are the most appropriate settings to calculate ClGdTPP coordinated with ligands. The dTP with ECP is the most computationally cost effective, i.e. optimal in the quality and convergence as well as time saving resource in contrast with large all-electron xQc especially in combination with ωB97XD that makes ωB97XD\u0026amp;xQc extremely time-consuming calculation. M062X\u0026amp;dTP without dispersion slightly and B3LYPD significantly underestimate Δ\u003cem\u003eG\u003c/em\u003e reactions whereas M06HFD\u0026amp;dTP overestimates Δ\u003cem\u003eG\u003c/em\u003e of the process. The other tested settings (see in SI) are inacceptable at all due to many unreasonable values.\u003c/p\u003e\u003cp\u003e\u003cem\u003eElectronic structures of ClGdTPP\u0026middot;kIm\u003c/em\u003e\u003c/p\u003e\u003cp\u003eElectronic structures of ClGdTPP\u0026middot;\u003cem\u003ek\u003c/em\u003eIm (\u003cem\u003ek\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0\u0026minus;2) were optimized with M062X\u0026amp;xQc, M062X\u0026amp;dTP and B3LYP\u0026amp;xQc for consideration. B3LYP\u0026amp;xQc produced the frontier β-UMO (lowest in energy unoccupied MO) formed almost absolutely by f-AO (Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e) that looks wrong because it should be π-MO according to the luminescence activity of the porphyrin compounds and computational researches using the other methods. M062X\u0026amp;dTP, using the ECP average in the basis set, can\u0026rsquo;t reproduce correctly all f-MOs for energetic schemes because this average over many deep AOs somehow involves and interacts with \u003cem\u003ef\u003c/em\u003e-types, resulting in unclear \u003cem\u003ef\u003c/em\u003e-MOs block and instead providing many mixed states, but this setting works well for the calculation of other properties, total energies and thermochemical reactions. The ClGdTPP\u0026middot;Im energy levels and numbering of MOs through dominantly Im localized and including all \u003cem\u003ef\u003c/em\u003e-types as well as their linear combinations of AOs calculated using M062X\u0026amp;xQc is analysed on Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\u003cp\u003eFrontier π-MOs are noted as ket-vectors |0〉\u0026thinsp;=\u0026thinsp;HOMO, |0\u0026prime;〉\u0026thinsp;=\u0026thinsp;LUMO and following MOs are numbered as |\u003cem\u003ej\u003c/em\u003e〉\u003csub\u003eα,β\u003c/sub\u003e and |\u003cem\u003ej\u003c/em\u003e\u0026prime;〉\u003csub\u003eα,β\u003c/sub\u003e, respectively, but spin subscription is omitted if MOs are the same type for both spins and close energy levels. More than two dozens of |\u003cem\u003ej\u003c/em\u003e\u0026ge;0〉\u003csub\u003eα,β\u003c/sub\u003e and |\u003cem\u003ej\u003c/em\u003e\u0026prime;\u0026ge;0〉\u003csub\u003eα,β\u003c/sub\u003e are π-types delocalized over porphyrin plane or on almost perpendicular to the terminate benzene rings and hardly mixed between the main and side cycles.\u003c/p\u003e\u003cp\u003eM062X\u0026amp;xQc provided some mixtures between \u003cem\u003ef\u003c/em\u003e-AOs and other AOs in linear combinations that led to 7 vacant MOs |19\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e\u0026minus;|25\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e with dominant, more than 66%, \u003cem\u003ef\u003c/em\u003e-AOs contribution and significant, about 30%, \u003cem\u003ef\u003c/em\u003e-AOs participation in 2 combinations of |18\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e, |26\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e with p,d AO vs 7 singly occupied MOs 96% strongly formed from \u003cem\u003ef\u003c/em\u003e-AOs but 88% with 1 slight p,s-AOs admixture |99〉\u003csub\u003eα\u003c/sub\u003e\u0026minus;|105〉\u003csub\u003eα\u003c/sub\u003e and |98〉\u003csub\u003eα\u003c/sub\u003e with only 22% \u003cem\u003ef\u003c/em\u003e-AO participation. The unoccupied \u003cem\u003ef\u003c/em\u003e-block is energetically laying much higher than many π-MO levels and even states based on d-AOs.\u003c/p\u003e\u003cp\u003eCoordination Gd-Im bond is short enough (2.58\u0026Aring;) to admix Gd d-AO with π-MOs of the moiety and the terminal benzene motives but not with perpendicular tetra-pyrrole plane. The |14\u0026prime;〉\u003csub\u003eα\u003c/sub\u003e MO localized almost exclusively on Im (92%) with insignificant benzene π-MO and gadolinium d-AO contributions. The |14\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e MO is the almost the same type but 79% Im participation with 11% d-AO contribution and a much less benzene π-MO admixture. d-AOs also notably contributes to unoccupied |9\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e 11% and maximum 22% to the similar |12\u0026prime;〉\u003csub\u003eβ\u003c/sub\u003e with Im-MO dominant such as for occupied |9〉\u003csub\u003eβ\u003c/sub\u003e and |12〉\u003csub\u003eβ\u003c/sub\u003e with nearly 6% both Gd and Cl d-AOs contributions. The |3\u0026prime;〉\u003csub\u003eα\u003c/sub\u003e and |7\u0026prime;〉\u003csub\u003eα\u003c/sub\u003e are significantly (81% and 39%) based on d-AO while there is no MO with dominantly localized on d-AO, instead it contributes to the nearest MOs in combination with \u003cem\u003ef\u003c/em\u003e-AOs and Im MOs.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eClGdTPP is more symmetrical (C\u003csub\u003e4\u003c/sub\u003e) than ClGdTPP\u0026middot;Im (C\u003csub\u003e1\u003c/sub\u003e) that provides degenerated states, in particular, several \u003cem\u003ef\u003c/em\u003e-MOs (Figure S2). One of \u003cem\u003ef\u003c/em\u003e-MOs splits and mixes with nearest and p and d (AO) orbitals, creating 6 pure \u003cem\u003ef\u003c/em\u003e-MOs and 2 MOs with significant participation of \u003cem\u003ef\u003c/em\u003e-AO. ClGdTPP\u0026middot;2Im (C\u003csub\u003e1\u003c/sub\u003e) provides the more complicate electronic structure which is richer than ClGdTPP\u0026middot;Im due to a higher number of Im moieties but it does not play a critical role in the order of the structure though more states with Im contributions are encountered because of stronger interaction with the main structure.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eElectronic structure and high multiplicities of ClGdTPP were calculated using the M062X and B3LYP functionals with the def2-SVP/def2-TZVP[Cl]/def2-TZVPP[Gd] and relativistic all-electron x2c-SVPall-2c/x2c-SVP-all[H]/x2c-TZVPall[Cl]/x2c-QZVPall-2c[Gd] basis sets to define energy levels and electron density shapes of the molecular orbitals which are the frontiers with the several nearest ones and the \u003cem\u003ef-\u003c/em\u003etype as well as localized on ligands.\u003c/p\u003e\u003cp\u003eMinnesota functionals family, ωB97XD, B3LYP and PBE0 with the same and SDDall basis sets were applied for the thermochemical analysis of ClGdTPP formation from GdCl\u003csub\u003e3\u003c/sub\u003e and H\u003csub\u003e2\u003c/sub\u003eTPP in molten imidazole. Enthalpies and Gibbs free energies of all possible coordination compounds of ClGdTPP with imidazole ligands (up to 2) and side products were compared. ClGdTPP\u0026sdot;2Im was found as the most energetically preferable complex formed in the reaction between H\u003csub\u003e2\u003c/sub\u003eTPP and GdCl\u003csub\u003e3\u003c/sub\u003e\u0026sdot;2Im in present of different numbers of extra free imidazole molecules. The ωB97XD\u0026amp;xQc, M062XD\u0026amp;xQc and M062XD\u0026amp;dTP functionals with the def2-SVP/def2-TZVP[Cl]/def2-TZVPP[Gd] and better x2c-SVPall-2c/x2c-SVP-all[H]/x2c-TZVPall[Cl]/x2c-QZVPall-2c[Gd] basis sets were defined as the most appropriate settings to calculate the electronic structures and thermochemical formations of ClGd-porphyrin family with ligands.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eV.P. conceptualized idea, obtained dates, wrote main text, prepared tables and figures.E.S. managed the project, wrote introduction, considered the main text, created figure 2.D.L. consulted on experimental data, discussed tables, figures. All authors discussed conclusions and reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eThe work was supported by Saint-Petersburg State University, project № 122040800256-8. The authors would like to thank the Computing Center of SPbU.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNi, Y. Metalloporphyrins and Functional Analogues as MRI Contrast Agents. \u003cem\u003eCMIR\u003c/em\u003e 2008, \u003cem\u003e4\u003c/em\u003e, 96\u0026ndash;112, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2174/157340508784356789\u003c/span\u003e\u003cspan address=\"10.2174/157340508784356789\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMironov, A.F. Lanthanide Porphyrin Complexes. \u003cem\u003eRuss. Chem. 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Local Coordination Numbers of up to 19 in Gadolinium\u0026ndash;Tin Alloy Nanoclusters. \u003cem\u003eThe Journal of Chemical Physics\u003c/em\u003e 2020, \u003cem\u003e153\u003c/em\u003e, 164308, doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1063/5.0027772\u003c/span\u003e\u003cspan address=\"10.1063/5.0027772\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"gadolinium, meso-tetraphenylporphyrin, quantum chemical calculations, DFT, thermochemistry, imidazole","lastPublishedDoi":"10.21203/rs.3.rs-7155766/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7155766/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe electronic structure and thermochemical formation of complex from gadolinium chloride and \u003cem\u003emeso\u003c/em\u003e-tetraphenylporphyrin in presence of imidazole molecules were calculated using the Minnesota functionals family, ωB97XD, B3LYP and PBE0 with the relativistic all-electron ahlrichs_x2c vs ahlrichs_def2 with ECP and SDDall basis sets. Enthalpies and Gibbs free energies of all possible formations of ClGdTPP coordinated with different numbers of imidazole ligands (up to 2) and side products were compared. The coordination compound ClGdTPP\u0026middot;2Im was found as the most energetically preferable complex of the discussed reaction in molten imidazole medium at high temperature. Electronic structures and high multiplicities of intermediate gadolinium compounds and final coordination complexes were considered in details.\u003c/p\u003e","manuscriptTitle":"Thermochemical transformations of gadolinium chloride and tetraphenylporphyrin into coordination complexes with imidazole ligands","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-01 16:38:32","doi":"10.21203/rs.3.rs-7155766/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"66054593-60f0-41af-a355-873f7785c994","owner":[],"postedDate":"September 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-09-23T14:23:48+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-01 16:38:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7155766","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7155766","identity":"rs-7155766","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}