{"paper_id":"1a9f0b6b-a7d1-4255-883d-9b162c1a388d","body_text":"Systematic Photophysical Interaction Studies Between Newly Synthesised Oxazole Derivatives and Silver Nanoparticles: Experimental and DFT Approach | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Systematic Photophysical Interaction Studies Between Newly Synthesised Oxazole Derivatives and Silver Nanoparticles: Experimental and DFT Approach Santosh R Mannopantar, V. S. Patil, Pavankumar Prabhala, A. S. Lalasangi, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-2951736/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 17 Aug, 2023 Read the published version in Journal of Fluorescence → Version 1 posted 9 You are reading this latest preprint version Abstract In this study, the photophysical properties of oxazole derivatives such as 5-(furan-2-yl) -4-tosyloxazole (OX-1) and 5-(2-bromothiazol-4-yl)-4-tosyloxazoles (OX-2) were investigated using theoretical and experimental techniques. The ground and excited state dipole moments were empirically obtained utilising the solvatochromic shift technique and several solvatochromic correlations such as Lippert's, Bakhshiev's, KawskiChamma- Viallet's, and solvent polarity equations. The ground state dipole moments, HOMO-LUMO and molecule electrostatic potential map were also computed using ab initio calculations and evaluated using Gaussian 09 W software. Furthermore, spectroscopic interactions between newly synthesised dyes (OX-1 and OX-2) and freshly synthesised silver nanoparticles (size 40 nm) were studied. Increased absorbance and widening of absorption spectra for both dyes in the presence of varied quantities of silver nanoparticles show the potential of dye-nanoparticle interactions. Fluorescence quenching has been detected for both dyes in the presence of colloidal silver nanoparticles, indicating dynamic quenching, and a significant overlap between the absorption and emission spectra of the silver nanoparticle reveals that fluorescence quenching is also due to energy transfer. Fluorescence quenching HOMO-LUMO MESP Ag nanoparticles Oxazole derivatives Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 1. Introduction Organic-inorganic hybrid materials, in which the organic and inorganic components are combined on the molecular level or nanoscale, have been attracting attention because of the synergetic effects that provide better performance than the simple sum of the individual contributions. Until now, a lot of effort for the fabrication and characterization of hybrid materials has been made, and there are now wide-ranging applications such as protective and decorative coatings, biocompatible materials, micro-optics, photovoltaic cells, etc. [ 1 – 4 ]. Inorganic nanoparticles, such as silver and gold show localized surface plasmon resonances (LSPRs) due to the collective excitation of conduction electrons by interacted with electromagnetic wave. Nanostructures that enable LSPRs are appealing for a variety of applications, including light control in thin-film solar cells, sensing via surface-enhanced Raman scattering, and plasmonic nanolasers, such as those derived from periodic particle arrays [ 5 – 7 ]. These applications capitalize on the fact that the LSPR excitation leads to a strong nanoscale concentration of electromagnetic energy [ 8 – 9 ]. Oxazoles are heterocycles with nitrogen and oxygen atoms in their five-member aromatic ring, and their structure facilitates noncovalent interactions with numerous enzymes and receptors of biological systems, allowing for a wide range of biological activities [ 10 ]. Compounds having a thiazole nucleus in their structure, on the other hand, have been extensively explored since this five-member aromatic ring containing sulphur and nitrogen atoms plays an important role in the construction of several medications, including the antineoplastic agents tiazofurin and dasatinib. [ 11 – 12 ]. Thiazoles, oxazole compounds, and their derivatives have been reported in the literature to exhibit a wide variety of biological activities, including antifungal, antiparasitic, and anti-inflammatory properties, as well as the most important anticancer actions [ 13 – 14 ]. In addition oxozole derivatives also show efficient optoelectronic properties [ 15 ]. In light of the foregoing, we devised a systematic and new approach for the synthesis of highly fluorescent oxazole derivatives and silver nanoparticles. Further, theoretical and experimental methodologies were used to investigate the spectroscopic interaction between silver nanoparticles and oxazole derivatives. 2. Experimental details The oxazole derivatives like OX-1 and OX-2 and structural data are published in our earlier publication [ 15 ]. The molecular structure of the oxazole derivatives is shown in Fig. 1. The solvent like Spectroscopic grade solvents used in the present study were procured from S. D. Fine Chem Ltd., India. Spectroscopic studies on the fluorophores were carried out maintaining the concentration of fluorescent probes at 10 −5 M. Absorption and fluorescence spectra of the fluorophores were recorded using Carry-300 UV-Vis spectrophotometer and Hitachi F-7000 fluorescence spectrophotometers, respectively. The geometric optimization, molecular electrostatic potential map and HOMO-LUMO of the compounds were carried out using B3LYP/6–31G method with help of the Gaussian 09 software package and the optimized structures of dyes were visualized by using the Gauss view 5.0 software [ 16 ]. 3. Results and discussion 3.1. Morphological analysis of silver nanoparticles HPMC capped Ag nanoparticles were synthesized by co precipitation method. The synthesized silver nanoparticles were characterized using powder XRD (p-XRD) and scanning electron microscopy (SEM). The p-XRD and SEM pattern of silver nanoparticles was depicted in Figs. 2 and 3. The XRD pattern shows that the peaks at about 38.1°, 44.09°, 64.36°, 77.29° and 81.31° for both the prepared materials, which corresponded to (111), (200), (220), (311), (222), (400), (331), and 420 planes, respectively, to indicate a typical face-centered cubic structure of silver as per the available literature (Joint Committee on Powder Diffraction Standards, JCPDS file No 04-0783). The SEM picture of silver nanoparticles indicates a particle size of 40 nm, which is consistent with the p-XRD results. 3.2. Photophysical studies The newly synthesized fluorophores (OX-1 and OX-2) absorption and fluorescence spectra were recorded in various solvents with variable polarity, and the spectra are displayed in Figs. 4–5. The value of absorption maximum ( \\({\\stackrel{-}{\\nu }}_{A}\\) ), fluorescence emission maximum ( \\({\\stackrel{-}{\\nu }}_{F}\\) ) and Stokes shift ( \\(\\varDelta \\stackrel{-}{v}\\) ) determined from absorption and emission spectra are given in supplementary file (Tables S1-2). From Figs. 4 and 5, it is observed that fluorescence maxima of the fluorophore show bathochromic shift of 337 to 344 nm and 351 to 378 nm for OX-1 and OX-2 respectively and this may be due to solute-solvent interactions affecting the charge distribution in excited state. The emission shift predominates over the absorption shift, indicating that the excited state dipole moment is enhanced. In addition, the good spectral band changes and Stokes shifts show intramolecular charge transfer (ICT) caused by the \\(\\pi \\to \\pi\\) * transition in the singlet excited state [ 17 ]. 3.3. Dipole moments The singlet excited state dipole moments of the synthesized compounds were determined by correlating their spectroscopic properties with Lippert-Mataga [ 18 – 19 ], Bakhshiev [ 20 ], Kawski-Chamma-Viallet [ 21 ] and Reichardt [ 22 ] solvent polarity functions and detailed explanations about these theories are given in supplementary file. The solvatochromic plots for OX-1 and OX-2 are presented in Figs. 6 a-d and the slopes, intercepts and correlation coefficients are given in Table-1. The values of ground state dipole moment ( \\({\\mu }_{g})\\) , excited state dipole moment ( \\({\\mu }_{e}\\) ), the ratio of the excited to ground state dipole moment ( \\({\\mu }_{e}/{\\mu }_{g}\\) ) and the change in dipole moments ( \\(\\varDelta \\mu\\) ) of the OX-1- and OX-2 were determined using the from various methods and are given in Tables 2 and 3. A considerable difference in ground and excited state dipole moment for both fluorophores indicate that significant charge distribution in the singlet excited state due to internal charge transfer process. Table-2 shows that excited state dipole moment is larger than the ground state dipole moment, indicating that the synthesised compounds are more polar in the excited state and also more sensitive to solvents. The variation in the excited state dipole moment value obtained from different solvatochromic methods is due to the various assumptions in the methods. Table-1 Solvent and fluorophore property correlation parameters Fluorophore Correlation Slope (cm −1 ) Intercept (cm −1 ) Correlation coefficient OX-1 Lippert-Mataga correlation 7637 5605 0.9089 Bakhshiev correlation 3115 5261 0.9557 Kawski-Chamma-Viallet correlation -1247 33410 0.9788 Reichardt correlation 4091 5099 0.9602 Lippert-Mataga correlation 3373 5363 0.9357 Bakhshiev correlation 1629 5091 0.9196 Kawski-Chamma-Viallet correlation -1015 31,743 0.9926 Reichardt correlation 1311 5303 0.9774 Table-2 Dipole moments of synthesised compounds Fluorophore \\(a\\) (Å) \\({\\mu }_{g}\\) (D) \\({\\mu }_{e}\\) (D) Lippert Bakhshiev Kawski-Chamma-Viallet Solvatochromic method Solvent polarity parameter OX-1 3.856 1.268 7.863 5.479 5.479 5.479 2.655 OX-2 3.974 2.378 6.963 5.564 5.564 5.564 1.573 Table-3 \\({\\mu }_{e}/{\\mu }_{g}\\) , \\(\\varphi\\) and \\(\\varDelta \\mu\\) of synthesised compound Fluorophore \\(\\frac{{\\mu }_{e}}{{\\mu }_{g}}\\) \\(\\varphi\\) (°) \\(\\varDelta \\mu\\) (D) Solvatochromic method Solvent polarity parameter OX-1 4.323 0 4.212 2.655 OX-2 2.340 0 3.187 1.573 While the Lippert technique, which does not account for polarizability, offers the greatest value of µ e , the solvent polarity parameter method, which considers particular solute-solvent interactions, yields the lowest value [ 23 ]. It is also discovered that OX-2 has a greater dipole moment than OX-1, indicating that OX-2 is more sensitive to solvent environment. The angle between dipoles in Table-3 shows that µ e and µ g is parallel, and the molecular symmetry is unaffected by electronic transition [ 24 ]. 3.4 Quantum chemical calculations 3.4.1 Frontier molecular orbitals The density functional theory with basis sets B3LYP/6-311G(d) in Gaussian 09W was also used to derive theoretical photophysical parameters. Figure 7 depicts the optimized ground state molecular structures with the dipole moment vectors of OX-1 and OX-2. Frontier molecular orbitals, HOMO and LUMO (Fig. 8 ), and molecular electrostatic potential map (Fig. 9) were used to assess the electronic structures and electron donor/acceptor capacities of the molecules and are computed using B3LYP/6-311G(d) in gas phase. The OX-1 and OX-2 ground state dipole moments are 3.529 D and 6.622 D, respectively. The synthesised compound's ground state dipole moment in gas phase is larger than the ground state dipole moment in the solvent phase which may be due to solvation effect of different solvents. 3.4.2 Global chemical reactivity descriptor (GCRD) parameters To gain insight on the chemical reactivity and stability of OX-1 and OX-2, global reactivity parameters, chemical hardness ( \\(\\eta =\\left(IP-EA\\right)/2\\) ), electronegativity ( \\(\\chi =\\left(IP+EA\\right)/2\\) ), chemical potential ( \\(\\mu =-\\chi\\) ), chemical softness ( \\(S=1/2\\eta\\) ) and electrophilicity index ( \\(\\omega ={\\mu }^{2}/2\\eta\\) ) were calculated from \\({E}_{HOMO}\\) and \\({E}_{LUMO}\\) values [ 25 ], where, ionization potential, \\(IP=-{E}_{HOMO}\\) and electron affinity, \\(EA=-{E}_{LUMO}\\) . The GCRD parameters of OX-1 and OX-2 are given in Table-4. While a wider HOMO–LUMO gap is connected with stability and hardness, a lesser HOMO–LUMO gap signifies a more reactive soft molecule which is highly polarizable. OX-1 is observed to be softer compared to OX-2 (Table-4) and this may be due to the electron withdrawing 2-bromothiazole moiety with asymmetrically linked oxazole. The presence of 2-bromothiazole furan group (electron acceptor) in OX-2 molecule leads to expansion of energy band gap as compared to OX-1 and LUMO electron cloud throughout the molecule which clearly displayed in Fig. 8 . These results suggest that, OX-2 is more reactive and less stable than OX-1. The electrophilicity index assesses the chemical reactivity of molecules [ 26 ]. Since on the ω scale, organic molecules with ω > 1.5 eV are classified as strong electrophiles, both fluorophores can be considered as good electrophiles [ 27 ]. The negative chemical potentials show that, the synthesized fluorophores are stable. The chemical hardness values indicate lesser deformation of the electron cloud of synthesized molecules under small perturbations. Table-4 GCRD parameter of synthesised molecules E HOMO (eV) E LUMO (eV) IP (eV) EA (eV) η (eV) χ (eV) µ (eV) S (eV) ω (eV) -6.228 -1.626 6.228 1.626 3.927 2.301 -3.927 0.217 3.351 -6.997 -2.324 6.997 2.324 4.661 2.337 -4.661 0.214 4.648 3.4.3. Molecular electrostatic potential (MESP) plots MESP maps constructed for synthesised compound via DFT-B3LYP/6-311G(d) model are shown in Fig. 9. The MESP maps show a range of colour (red to dark blue) representing extreme negative (nucleophilic) to positive (electrophilic) locations on the molecule. In both the molecule the strong positive phase (dark blue region) appears on toluene and oxazole ring and strong negative phase around the nitrogen and oxygen atoms. Based on the GCRD and MESP parameters, it is obvious that the synthesised molecule has a broad energy band gap and good chemical stability, implying that these molecules might be used as an emissive layer in OLEDs. Because silver is the most often used contact electrode in OLEDs, fluorescence quenching of synthesised molecules was investigated using silver nanoparticles to better understand the electron transfer process. 3.5. Absorption Characteristics of Oxazole Derivatives in Ag nanoparticles: Figures 10 and 11 show the UV-vis absorption spectrum of OX-1 and OX-2 with silver nanoparticles. The absorption spectra of OX-1 and OX-2 in ethanol with and without silver nanoparticles. With different concentrations of silver nanoparticles, the absorption spectra of the oxazole derivatives were boosted and broadened without shift in the absorption maxima peak, as shown in Figs. 10 and 11 . This demonstrates that dyes interact with silver nanoparticles, resulting in the development of a ground state complex. Stern-Volmer (S-V) plots were generated using steady state techniques to elucidate the fluorescence quenching process between dyes and silver nanoparticles, as illustrated in Fig. 12 . $$\\frac{{I}_{0}}{I}=1+{k}_{sv} Q$$ 1 Where, k SV are the steady-state Stern-Volmer quenching constants. The k q values represent the characteristics of the bimolecular quenching rate. The S-V plots using steady-state techniques are shown to be linear for all dyes, with high correlation coefficients (r) close to unity (see Fig. 15 ). This strongly implies that the quenching is the result of dynamic or collisional quenching. Table-5 shows the slopes, intercepts, and correlation coefficients obtained from S-V plots. Table-5 shows that the values of the Stern-Volmer constants are in the same range as the previously published values [ 28 – 29 ]. Table-5 shows the value of S-V constant (K sv ), bimolecular quenching constant (K q ) and association constant (K s ) Sample S-V plot B-H plot τ 0 (ns) k sv x10 5 M − 1 K q x10 14 M − 1 s − 1 r 2 Slope x10 − 10 M Intercept x10 − 4 r 2 K s x10 6 M − 1 OX-1 1.32 1.292 0.978 0.987 9.619 1.164 0.984 0.001 OX-2 1.45 2.421 1.644 0.933 10.984 21.646 0.999 1.974 3.6. Binding mode studies Using the Benesi–Hilderbrand [30] equation stoichiometry and the binding or association constant (KS) of the solute with silver nanoparticles are estimated from the following equation, $$\\frac{1}{{I}_{0}-I}=\\frac{1}{{K}_{s}\\left[C\\right]Q}+\\frac{1}{\\left[C\\right]}$$ 2 In this equation, I and I 0 represent the fluorescence intensity of a solute with and without silver nanoparticles, respectively. Where Ks, [C], and Q denote the association constant, dye concentration, and nanoparticle concentration, respectively. Figure 15 depicts 1/Q Vs 1/(I-I0) graphs for all dye-silver nanoparticles systems. Because all the charts are precisely linear, they give proof of 1:1 stoichiometry. The association constant (KS) is computed as the ratio of intercept to slope, and the values are shown in Table-5. The findings show that the synthesised molecule has a high affinity for silver nanoparticles. 3.7. Role of Energy Transfer in Fluorescence Quenching The spectral overlap between the nanoparticle absorption and dye emission spectra suggests the possibility of energy transfer. Forster's non-radiative energy transfer hypothesis explains the function of energy transfer in the fluorescence quenching of dyes by silver nanoparticles. Energy transfer occurs under the following circumstances, according to this theory: (a) the donor may produce fluorescence, (b) the emission spectrum of the donor and the absorption spectrum of the acceptor have greater overlap, and (c) the distance between the donor and the acceptor is less than 70 [ 31 ]. Figure 16 depicts the overlap of the absorption spectrum of silver nanoparticles with the emission spectra of OX-1 and OX-2. As a result, energy transmission between dye molecules and silver nanoparticles is possible. Forster Eq. 3 [ 31 ] gives the critical energy transfer distance in angstroms when the energy transfer efficiency is 50% (R 0 ). where k 2 (2/3) is the orientation factor relating the geometry of donor–acceptor dipoles, n (= 1.33) is the refractive index of methanol, \\({\\phi }_{0}\\) is the fluorescence quantum yield of oxazole dye (OX-1 = 0.53 and OX-2 = 0.58) and J is the overlap integral between donor emission and acceptor absorption. The values of J can be calculated using Eq. ( 4 ) [ 31 ]: $$J={\\int }_{0}^{\\infty }{F}_{d}\\left(\\lambda \\right){\\epsilon }_{d}\\left(\\lambda \\right){\\lambda }^{4}d\\lambda$$ 4 where \\({F}_{d}\\left(\\lambda \\right)\\) is the fluorescence intensity of the donor in the wavelength range to d, with total intensity normalized to unity, and \\({\\epsilon }_{d}\\left(\\lambda \\right)\\) is the acceptor's extinction co-efficient at λ. Table-6 shows the values of the oxazole's overlap integral value. The integral value of the crucial transfer distance is determined using the value overlap and is found to be 28.142 Å and 34.985 Å for OX-1 and OX-2, respectively and are shown in Table-6. The findings show that fluorescence quenching is also caused by nonradiative energy transfer from the dye to the silver nanoparticles. Table-6 the value of overlap integral and critical transfer distance Sample J (M − 1 cm − 1 nm 4 ) R 0 (Å) OX-1 7.331 28.142 OX-2 9.812 34.985 4. Conclusions The photophysical characteristics of the new oxazole derivatives OX-1 and OX-2 were investigated utilizing experimental and theoretical approaches. The ground and excited state dipole moments were empirically obtained using the Lippert’s, Bakhshiev's, KawskiChamma- Viallet's, and solvent polarity equations and result suggest that synthesised molecules are more polar in excited sate than ground state. The ground state dipole moments, HOMO-LUMO, and molecule electrostatic potential map were also computed using ab initio calculations. Furthermore, spectroscopic interactions between newly synthesised dyes (OX-1 and OX-2) and freshly synthesised silver nanoparticles (size 40 nm) were studied. Increased absorbance and widening of absorption spectra for both dyes in the presence of varied quantities of silver nanoparticles show the potential of dye-nanoparticle interactions. Fluorescence quenching has been detected for both dyes in the presence of colloidal silver nanoparticles, indicating dynamic quenching, and a significant overlap between the absorption and emission spectra of the silver nanoparticle reveals that fluorescence quenching is also due to energy transfer. Declarations Ethical Approval : Not applicable Competing interests : Declared competing interest Authors' contributions : Santosh R Mannopantar :Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Resources; Software; Supervision; Validation; Visualization; Roles/Writing - original draft; Writing - review & editing. V. S. Patil : Data curation; Formal analysis; M N Kalasad : Visualization; Roles/Writing - original draft; Writing - review &editing. Pavan Prabhala : Formal analysis; Investigation; Methodology; Resources A. S. Lalasangi : Data curation; Formal analysis; V. K. Kulkarni : Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Resources; Software; Supervision; Validation; Visualization; Roles/Writing - original draft; Writing - review & editing. Funding: Not applicable Availability of data and materials : All data can be accessed. References Chen, Y., & Shi, J. (2016). Chemistry of mesoporous organosilica in nanotechnology: molecularly organic–inorganic hybridization into frameworks. Advanced Materials, 28(17), 3235-3272. Chen, G., Qian, Y., Zhang, H., Ullah, A., He, X., Zhou, Z., ... & Shen, J. (2021). Advances in cancer theranostics using organic-inorganic hybrid nanotechnology. Applied Materials Today, 23, 101003. Yao, H. B., Gao, M. R., & Yu, S. H. (2010). Small organic molecule templating synthesis of organic–inorganic hybrid materials: their nanostructures and properties. Nanoscale, 2(3), 322-334. Park, W., Shin, H., Choi, B., Rhim, W. K., Na, K., & Han, D. K. (2020). 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Supplementary Files Supplimentryfiles.docx Cite Share Download PDF Status: Published Journal Publication published 17 Aug, 2023 Read the published version in Journal of Fluorescence → Version 1 posted Editorial decision: Major revision 20 Jun, 2023 Reviews received at journal 18 Jun, 2023 Reviewers agreed at journal 13 Jun, 2023 Reviewers agreed at journal 25 May, 2023 Reviewers agreed at journal 25 May, 2023 Reviewers invited by journal 25 May, 2023 Editor assigned by journal 23 May, 2023 Submission checks completed at journal 23 May, 2023 First submitted to journal 18 May, 2023 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. 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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-2951736\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":202950582,\"identity\":\"15819e1b-1180-41fc-b641-c0c9f642cff5\",\"order_by\":0,\"name\":\"Santosh R Mannopantar\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Government First Grade College, Kalaghatagi\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Santosh\",\"middleName\":\"R\",\"lastName\":\"Mannopantar\",\"suffix\":\"\"},{\"id\":202950583,\"identity\":\"26886ad8-f2fb-4ddc-8781-129e7ac60951\",\"order_by\":1,\"name\":\"V. S. Patil\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Davangere University\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"V.\",\"middleName\":\"S.\",\"lastName\":\"Patil\",\"suffix\":\"\"},{\"id\":202950584,\"identity\":\"bc6787d4-433e-466f-8f15-491735c21d68\",\"order_by\":2,\"name\":\"Pavankumar Prabhala\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Karnatak Science College, Dharwad\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Pavankumar\",\"middleName\":\"\",\"lastName\":\"Prabhala\",\"suffix\":\"\"},{\"id\":202950585,\"identity\":\"11992565-85d7-4c65-8b54-983658e26c4c\",\"order_by\":3,\"name\":\"A. S. Lalasangi\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Smt. I.S yadawad GFGC\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"A.\",\"middleName\":\"S.\",\"lastName\":\"Lalasangi\",\"suffix\":\"\"},{\"id\":202950586,\"identity\":\"6340844c-dafd-46d8-9d5b-a45f5548715f\",\"order_by\":4,\"name\":\"M. N. Kalasad\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Davangere University\",\"correspondingAuthor\":false,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"M.\",\"middleName\":\"N.\",\"lastName\":\"Kalasad\",\"suffix\":\"\"},{\"id\":202950587,\"identity\":\"7c762e4a-0c24-4fd9-a4c0-64fa6b336dee\",\"order_by\":5,\"name\":\"Vijay. K. Kulkarni\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA2ElEQVRIiWNgGAWjYDACZoYEBoYDDIz9IE5CASlaZjaAtBgQbRVQy4YDIAYxWgyOMzz8zHPmsOzm86sTPzwwYJDnFztAQMthhmRpnhuHjbfdeLtZAugww5mzE/BrkWxmSJDm+XA4cduNsxtAWhIMbhPWkvwbpGXzjLObfxClhZ+ZIQ3ksMQN/L3biLMFpMVyzpl04xk3eLdZJBhIEPYLG/+Z5BtvjlnL9vef3XzzR4WNPL80AS0MDDwJTDwgWgKsUoKQchBgP8D4A+zEA8SoHgWjYBSMgpEIAHCnScA+ph0fAAAAAElFTkSuQmCC\",\"orcid\":\"\",\"institution\":\"Angadi Institute of Technology and Management Belagavi\",\"correspondingAuthor\":true,\"submittingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Vijay.\",\"middleName\":\"K.\",\"lastName\":\"Kulkarni\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2023-05-18 10:29:24\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-2951736/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-2951736/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1007/s10895-023-03369-y\",\"type\":\"published\",\"date\":\"2023-08-17T22:00:24+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":37444680,\"identity\":\"093a1bca-9425-496b-9973-239c76388261\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:57\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":47332,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eMolecular structure of (a) OX-1 and (b) OX-2.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/3fadbc818aadb615da3a6c31.png\"},{\"id\":37445525,\"identity\":\"2e76d43f-e366-4405-8034-0f0afa01098e\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:40:57\",\"extension\":\"png\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":17779,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eThe powder XRD pattern of silver nanoparticles.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"2.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/e1f501f591aa61de3fd20161.png\"},{\"id\":37444689,\"identity\":\"d038098b-cdda-47d3-853d-adf5af55e72e\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:57\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":293863,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003e(a) SEM image and (b) EDAX pattern of silver nano particles.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"3.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/73655d1db4c8860b78dbc887.png\"},{\"id\":37447808,\"identity\":\"a8c48baa-cec3-4541-80cc-d3bea3da84e6\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 16:04:57\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":103710,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eNormalized absorption (a) and fluorescence spectra (b) of OX-1 in different solvents.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/e89d56da3ee8732a4897b78b.png\"},{\"id\":37446493,\"identity\":\"18e6c3e6-72cd-41da-b9b7-11f7fcf15b93\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:48:57\",\"extension\":\"png\",\"order_by\":5,\"title\":\"Figure 5\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":91636,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eNormalized absorption (a) and fluorescence spectra (b) of OX-2 in different solvents.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/b461ac9e6ee93c36f622ab60.png\"},{\"id\":37446494,\"identity\":\"3643b606-386f-4172-a055-538350a1cc4b\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:48:57\",\"extension\":\"png\",\"order_by\":6,\"title\":\"Figure 6\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":85159,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eSee image above for figure legend\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"6.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/a21c02516bb002495cb1dde9.png\"},{\"id\":37445528,\"identity\":\"00d316d4-d759-44b7-b23a-901ad5c72cba\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:40:57\",\"extension\":\"png\",\"order_by\":7,\"title\":\"Figure 7\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":56660,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eOptimised ground state molecular structure with dipole moment vector for (a) and (b).\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"7.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/2f1f6ccb2f61ad378ff61d63.png\"},{\"id\":37447381,\"identity\":\"1a84012c-ad8d-4032-8288-004b40c06590\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:56:57\",\"extension\":\"png\",\"order_by\":8,\"title\":\"Figure 8\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":58800,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003e3D plots of HOMO and LUMO of the synthesized dyes.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"8.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/5ecdb58cb3ee9f1ee028028f.png\"},{\"id\":37444693,\"identity\":\"70f4519d-0bdc-4d3c-86f1-3630981773aa\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:57\",\"extension\":\"png\",\"order_by\":9,\"title\":\"Figure 9\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":315891,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eMESP plots for (a) OX-1 and (b) OX-2.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"9.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/2038e98eb161f4b7362af6e0.png\"},{\"id\":37444683,\"identity\":\"e5ee77a2-999b-4acf-b5fa-e77c0567d703\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:57\",\"extension\":\"png\",\"order_by\":10,\"title\":\"Figure 10\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":16335,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eAbsorption spectra of OX-1 with varying concentration of silver nanoparticles\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"10.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/f38f4b46f266f0bec3575de6.png\"},{\"id\":37445534,\"identity\":\"941e81ab-1ada-48c9-8471-81bf680afef6\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:40:58\",\"extension\":\"png\",\"order_by\":11,\"title\":\"Figure 11\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":19781,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eAbsorption spectra of OX-2 with varying concentration of silver nanoparticle.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"11.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/75c2b975b02ea8d3c60b74a1.png\"},{\"id\":37446497,\"identity\":\"5b54e248-d1cd-49ec-b0da-e4ead2afb0ed\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:48:57\",\"extension\":\"png\",\"order_by\":12,\"title\":\"Figure 12\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":21545,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eFluorescence spectra of OX-1 with varying concentration of silver nanoparticles\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"12.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/bad3f7c5b2afdbe9dcadacff.png\"},{\"id\":37447382,\"identity\":\"16004ce5-f703-4ecb-beaa-89c7104a41ea\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:56:57\",\"extension\":\"png\",\"order_by\":13,\"title\":\"Figure 13\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":24878,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eFluorescence spectra of OX-1 with varying concentration of silver nanoparticles.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"13.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/ea698e92c6cf2e4f4d7c2e34.png\"},{\"id\":37447383,\"identity\":\"572831f4-a16b-4386-a56f-12694fb79da5\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:56:58\",\"extension\":\"png\",\"order_by\":14,\"title\":\"Figure 14\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":14497,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eS-V plot of the oxazole derivatives.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"14.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/80c7beafa0f3e4cfcff928a8.png\"},{\"id\":37444696,\"identity\":\"1d65a6e5-b98e-447d-8048-1e61b19b7e6c\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:58\",\"extension\":\"png\",\"order_by\":15,\"title\":\"Figure 15\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":11424,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eB-H plot for oxazole derivatives\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"15.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/b88d636b34b5787946c0a6bb.png\"},{\"id\":37444695,\"identity\":\"8ecf4fd8-7c1a-4d3b-bdaf-31542c993ed2\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:58\",\"extension\":\"png\",\"order_by\":16,\"title\":\"Figure 16\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":17020,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eOverlap of absorption spectrum of silver nanoparticles with emission spectra of OX-1 and OX-2.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"16.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/0ba5a37e14a5ecda6bb9202d.png\"},{\"id\":44735646,\"identity\":\"1a1c6fbc-3151-43ff-918e-7af2f363c9ba\",\"added_by\":\"auto\",\"created_at\":\"2023-10-16 22:26:34\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1865124,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/a46d8d56-057d-4ee5-9ddb-b7423c6fafc7.pdf\"},{\"id\":37444684,\"identity\":\"d273891c-94f2-454a-a289-eb3cf89c7a3c\",\"added_by\":\"auto\",\"created_at\":\"2023-05-24 15:32:57\",\"extension\":\"docx\",\"order_by\":1,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"supplement\",\"size\":30126,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"Supplimentryfiles.docx\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-2951736/v1/b160a86ae0554f10f27e340b.docx\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Systematic Photophysical Interaction Studies Between Newly Synthesised Oxazole Derivatives and Silver Nanoparticles: Experimental and DFT Approach\",\"fulltext\":[{\"header\":\"1. Introduction\",\"content\":\"\\u003cp\\u003eOrganic-inorganic hybrid materials, in which the organic and inorganic components are combined on the molecular level or nanoscale, have been attracting attention because of the synergetic effects that provide better performance than the simple sum of the individual contributions. Until now, a lot of effort for the fabrication and characterization of hybrid materials has been made, and there are now wide-ranging applications such as protective and decorative coatings, biocompatible materials, micro-optics, photovoltaic cells, etc. [\\u003cspan additionalcitationids=\\\"CR2 CR3\\\" citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e]. Inorganic nanoparticles, such as silver and gold show localized surface plasmon resonances (LSPRs) due to the collective excitation of conduction electrons by interacted with electromagnetic wave. Nanostructures that enable LSPRs are appealing for a variety of applications, including light control in thin-film solar cells, sensing \\u003cem\\u003evia\\u003c/em\\u003e surface-enhanced Raman scattering, and plasmonic nanolasers, such as those derived from periodic particle arrays [\\u003cspan additionalcitationids=\\\"CR6\\\" citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e]. These applications capitalize on the fact that the LSPR excitation leads to a strong nanoscale concentration of electromagnetic energy [\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eOxazoles are heterocycles with nitrogen and oxygen atoms in their five-member aromatic ring, and their structure facilitates noncovalent interactions with numerous enzymes and receptors of biological systems, allowing for a wide range of biological activities [\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]. Compounds having a thiazole nucleus in their structure, on the other hand, have been extensively explored since this five-member aromatic ring containing sulphur and nitrogen atoms plays an important role in the construction of several medications, including the antineoplastic agents tiazofurin and dasatinib. [\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e]. Thiazoles, oxazole compounds, and their derivatives have been reported in the literature to exhibit a wide variety of biological activities, including antifungal, antiparasitic, and anti-inflammatory properties, as well as the most important anticancer actions [\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]. In addition oxozole derivatives also show efficient optoelectronic properties [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eIn light of the foregoing, we devised a systematic and new approach for the synthesis of highly fluorescent oxazole derivatives and silver nanoparticles. Further, theoretical and experimental methodologies were used to investigate the spectroscopic interaction between silver nanoparticles and oxazole derivatives.\\u003c/p\\u003e\"},{\"header\":\"2. Experimental details\",\"content\":\"\\u003cp\\u003eThe oxazole derivatives like OX-1 and OX-2 and structural data are published in our earlier publication [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]. The molecular structure of the oxazole derivatives is shown in Fig.\\u0026nbsp;1. The solvent like Spectroscopic grade solvents used in the present study were procured from S. D. Fine Chem Ltd., India. Spectroscopic studies on the fluorophores were carried out maintaining the concentration of fluorescent probes at 10\\u003csup\\u003e\\u0026minus;5\\u003c/sup\\u003e M. Absorption and fluorescence spectra of the fluorophores were recorded using Carry-300 UV-Vis spectrophotometer and Hitachi F-7000 fluorescence spectrophotometers, respectively. The geometric optimization, molecular electrostatic potential map and HOMO-LUMO of the compounds were carried out using B3LYP/6\\u0026ndash;31G method with help of the Gaussian 09 software package and the optimized structures of dyes were visualized by using the Gauss view 5.0 software [\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e].\\u003c/p\\u003e \"},{\"header\":\"3. Results and discussion\",\"content\":\"\\u003cdiv id=\\\"Sec4\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.1. Morphological analysis of silver nanoparticles\\u003c/h2\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eHPMC capped Ag nanoparticles were synthesized by co precipitation method. The synthesized silver nanoparticles were characterized using powder XRD (p-XRD) and scanning electron microscopy (SEM). The p-XRD and SEM pattern of silver nanoparticles was depicted in Figs.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e and 3. The XRD pattern shows that the peaks at about 38.1\\u0026deg;, 44.09\\u0026deg;, 64.36\\u0026deg;, 77.29\\u0026deg; and 81.31\\u0026deg; for both the prepared materials, which corresponded to (111), (200), (220), (311), (222), (400), (331), and 420 planes, respectively, to indicate a typical face-centered cubic structure of silver as per the available literature (Joint Committee on Powder Diffraction Standards, JCPDS file No 04-0783).\\u003c/p\\u003e \\u003cp\\u003eThe SEM picture of silver nanoparticles indicates a particle size of 40 nm, which is consistent with the p-XRD results.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec5\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.2. Photophysical studies\\u003c/h2\\u003e \\u003cp\\u003eThe newly synthesized fluorophores (OX-1 and OX-2) absorption and fluorescence spectra were recorded in various solvents with variable polarity, and the spectra are displayed in Figs.\\u0026nbsp;4\\u0026ndash;5. The value of absorption maximum (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\stackrel{-}{\\\\nu }}_{A}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e), fluorescence emission maximum (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\stackrel{-}{\\\\nu }}_{F}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) and Stokes shift (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varDelta \\\\stackrel{-}{v}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) determined from absorption and emission spectra are given in supplementary file (Tables S1-2). From Figs.\\u0026nbsp;4 and 5, it is observed that fluorescence maxima of the fluorophore show bathochromic shift of 337 to 344 nm and 351 to 378 nm for OX-1 and OX-2 respectively and this may be due to solute-solvent interactions affecting the charge distribution in excited state. The emission shift predominates over the absorption shift, indicating that the excited state dipole moment is enhanced. In addition, the good spectral band changes and Stokes shifts show intramolecular charge transfer (ICT) caused by the \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\pi \\\\to \\\\pi\\\\)\\u003c/span\\u003e\\u003c/span\\u003e\\u003cem\\u003e*\\u003c/em\\u003e transition in the singlet excited state [\\u003cspan citationid=\\\"CR17\\\" class=\\\"CitationRef\\\"\\u003e17\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cdiv id=\\\"Sec6\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.3. Dipole moments\\u003c/h2\\u003e \\u003cp\\u003eThe singlet excited state dipole moments of the synthesized compounds were determined by correlating their spectroscopic properties with Lippert-Mataga [\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR19\\\" class=\\\"CitationRef\\\"\\u003e19\\u003c/span\\u003e], Bakhshiev [\\u003cspan citationid=\\\"CR20\\\" class=\\\"CitationRef\\\"\\u003e20\\u003c/span\\u003e], Kawski-Chamma-Viallet [\\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e21\\u003c/span\\u003e] and Reichardt [\\u003cspan citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e22\\u003c/span\\u003e] solvent polarity functions and detailed explanations about these theories are given in supplementary file. The solvatochromic plots for OX-1 and OX-2 are presented in Figs.\\u0026nbsp;\\u003cspan refid=\\\"Fig4\\\" class=\\\"InternalRef\\\"\\u003e6\\u003c/span\\u003ea-d and the slopes, intercepts and correlation coefficients are given in Table-1.\\u003c/p\\u003e \\u003cp\\u003eThe values of ground state dipole moment (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{g})\\\\)\\u003c/span\\u003e\\u003c/span\\u003e, excited state dipole moment (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{e}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e), the ratio of the excited to ground state dipole moment \\u003cem\\u003e(\\u003c/em\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{e}/{\\\\mu }_{g}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) and the change in dipole moments (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varDelta \\\\mu\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) of the OX-1- and OX-2 were determined using the from various methods and are given in Tables\\u0026nbsp;2 and 3. A considerable difference in ground and excited state dipole moment for both fluorophores indicate that significant charge distribution in the singlet excited state due to internal charge transfer process. Table-2 shows that excited state dipole moment is larger than the ground state dipole moment, indicating that the synthesised compounds are more polar in the excited state and also more sensitive to solvents. The variation in the excited state dipole moment value obtained from different solvatochromic methods is due to the various assumptions in the methods.\\u003c/p\\u003e \\u003cp\\u003eTable-1 Solvent and fluorophore property correlation parameters\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabe\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"5\\\"\\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=\\\"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 \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eFluorophore\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eCorrelation\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eSlope\\u003c/p\\u003e \\u003cp\\u003e(cm\\u003csup\\u003e\\u0026minus;1\\u003c/sup\\u003e)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eIntercept\\u003c/p\\u003e \\u003cp\\u003e(cm\\u003csup\\u003e\\u0026minus;1\\u003c/sup\\u003e)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eCorrelation coefficient\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"3\\\" rowspan=\\\"4\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eOX-1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eLippert-Mataga correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e7637\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5605\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9089\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eBakhshiev correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e3115\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5261\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9557\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eKawski-Chamma-Viallet correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e-1247\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e33410\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9788\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eReichardt correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e4091\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5099\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9602\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"3\\\" rowspan=\\\"4\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eLippert-Mataga correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e3373\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5363\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9357\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eBakhshiev correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1629\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5091\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9196\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eKawski-Chamma-Viallet correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e-1015\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e31,743\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9926\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eReichardt correlation\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1311\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5303\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9774\\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\\u003eTable-2 Dipole moments of synthesised compounds\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabf\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" 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 \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eFluorophore\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(a\\\\)\\u003c/span\\u003e\\u003c/span\\u003e (\\u0026Aring;)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{g}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e (D)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"5\\\" nameend=\\\"c8\\\" namest=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{e}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e (D)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eLippert\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eBakhshiev\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eKawski-Chamma-Viallet\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eSolvatochromic method\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003eSolvent polarity parameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eOX-1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e3.856\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1.268\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e7.863\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e5.479\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5.479\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e5.479\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.655\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eOX-2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e3.974\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2.378\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e6.963\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e5.564\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5.564\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e5.564\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.573\\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\\u003eTable-3 \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\mu }_{e}/{\\\\mu }_{g}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varphi\\\\)\\u003c/span\\u003e\\u003c/span\\u003e and \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varDelta \\\\mu\\\\)\\u003c/span\\u003e\\u003c/span\\u003e of synthesised compound\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabg\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"5\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" 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 \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eFluorophore\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\frac{{\\\\mu }_{e}}{{\\\\mu }_{g}}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varphi\\\\)\\u003c/span\\u003e\\u003c/span\\u003e (\\u0026deg;)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c5\\\" namest=\\\"c4\\\"\\u003e \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\varDelta \\\\mu\\\\)\\u003c/span\\u003e\\u003c/span\\u003e (D)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eSolvatochromic method\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eSolvent polarity parameter\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eOX-1\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e4.323\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4.212\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e2.655\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eOX-2\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2.340\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.187\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.573\\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\\u003eWhile the Lippert technique, which does not account for polarizability, offers the greatest value of \\u0026micro;\\u003csub\\u003ee\\u003c/sub\\u003e, the solvent polarity parameter method, which considers particular solute-solvent interactions, yields the lowest value [\\u003cspan citationid=\\\"CR23\\\" class=\\\"CitationRef\\\"\\u003e23\\u003c/span\\u003e]. It is also discovered that OX-2 has a greater dipole moment than OX-1, indicating that OX-2 is more sensitive to solvent environment. The angle between dipoles in Table-3 shows that \\u0026micro;\\u003csub\\u003ee\\u003c/sub\\u003e and \\u0026micro;\\u003csub\\u003eg\\u003c/sub\\u003e is parallel, and the molecular symmetry is unaffected by electronic transition [\\u003cspan citationid=\\\"CR24\\\" class=\\\"CitationRef\\\"\\u003e24\\u003c/span\\u003e].\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec7\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.4 Quantum chemical calculations\\u003c/h2\\u003e \\u003cdiv id=\\\"Sec8\\\" class=\\\"Section3\\\"\\u003e \\u003ch2\\u003e3.4.1 Frontier molecular orbitals\\u003c/h2\\u003e \\u003cp\\u003eThe density functional theory with basis sets B3LYP/6-311G(d) in Gaussian 09W was also used to derive theoretical photophysical parameters. Figure\\u0026nbsp;7 depicts the optimized ground state molecular structures with the dipole moment vectors of OX-1 and OX-2. Frontier molecular orbitals, HOMO and LUMO (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig5\\\" class=\\\"InternalRef\\\"\\u003e8\\u003c/span\\u003e), and molecular electrostatic potential map (Fig.\\u0026nbsp;9) were used to assess the electronic structures and electron donor/acceptor capacities of the molecules and are computed using B3LYP/6-311G(d) in gas phase. The OX-1 and OX-2 ground state dipole moments are 3.529 D and 6.622 D, respectively. The synthesised compound's ground state dipole moment in gas phase is larger than the ground state dipole moment in the solvent phase which may be due to solvation effect of different solvents.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec9\\\" class=\\\"Section3\\\"\\u003e \\u003ch2\\u003e3.4.2 Global chemical reactivity descriptor (GCRD) parameters\\u003c/h2\\u003e \\u003cp\\u003eTo gain insight on the chemical reactivity and stability of OX-1 and OX-2, global reactivity parameters, chemical hardness (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\eta =\\\\left(IP-EA\\\\right)/2\\\\)\\u003c/span\\u003e\\u003c/span\\u003e), electronegativity (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\chi =\\\\left(IP+EA\\\\right)/2\\\\)\\u003c/span\\u003e\\u003c/span\\u003e), chemical potential (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\mu =-\\\\chi\\\\)\\u003c/span\\u003e\\u003c/span\\u003e), chemical softness (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(S=1/2\\\\eta\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) and electrophilicity index (\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\omega ={\\\\mu }^{2}/2\\\\eta\\\\)\\u003c/span\\u003e\\u003c/span\\u003e) were calculated from \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({E}_{HOMO}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e and \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({E}_{LUMO}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e values [\\u003cspan citationid=\\\"CR25\\\" class=\\\"CitationRef\\\"\\u003e25\\u003c/span\\u003e], where, ionization potential, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(IP=-{E}_{HOMO}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e and electron affinity, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(EA=-{E}_{LUMO}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e. The GCRD parameters of OX-1 and OX-2 are given in Table-4. While a wider HOMO\\u0026ndash;LUMO gap is connected with stability and hardness, a lesser HOMO\\u0026ndash;LUMO gap signifies a more reactive soft molecule which is highly polarizable. OX-1 is observed to be softer compared to OX-2 (Table-4) and this may be due to the electron withdrawing 2-bromothiazole moiety with asymmetrically linked oxazole. The presence of 2-bromothiazole furan group (electron acceptor) in OX-2 molecule leads to expansion of energy band gap as compared to OX-1 and LUMO electron cloud throughout the molecule which clearly displayed in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig5\\\" class=\\\"InternalRef\\\"\\u003e8\\u003c/span\\u003e. These results suggest that, OX-2 is more reactive and less stable than OX-1. The electrophilicity index assesses the chemical reactivity of molecules [\\u003cspan citationid=\\\"CR26\\\" class=\\\"CitationRef\\\"\\u003e26\\u003c/span\\u003e]. Since on the ω scale, organic molecules with ω\\u0026thinsp;\\u0026gt;\\u0026thinsp;1.5 eV are classified as strong electrophiles, both fluorophores can be considered as good electrophiles [\\u003cspan citationid=\\\"CR27\\\" class=\\\"CitationRef\\\"\\u003e27\\u003c/span\\u003e]. The negative chemical potentials show that, the synthesized fluorophores are stable. The chemical hardness values indicate lesser deformation of the electron cloud of synthesized molecules under small perturbations.\\u003c/p\\u003e \\u003cp\\u003eTable-4 GCRD parameter of synthesised molecules\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabi\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"9\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" 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 \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c9\\\" colnum=\\\"9\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eE\\u003csub\\u003eHOMO\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eE\\u003csub\\u003eLUMO\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eIP\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eEA\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eη\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eχ\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e\\u0026micro;\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003eS\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003eω\\u003c/p\\u003e \\u003cp\\u003e(eV)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e-6.228\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e-1.626\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e6.228\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1.626\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e3.927\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e2.301\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e-3.927\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.217\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e3.351\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e-6.997\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e-2.324\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e6.997\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.324\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e4.661\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e2.337\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e-4.661\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.214\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e4.648\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec10\\\" class=\\\"Section3\\\"\\u003e \\u003ch2\\u003e3.4.3. Molecular electrostatic potential (MESP) plots\\u003c/h2\\u003e \\u003cp\\u003eMESP maps constructed for synthesised compound via DFT-B3LYP/6-311G(d) model are shown in Fig.\\u0026nbsp;9. The MESP maps show a range of colour (red to dark blue) representing extreme negative (nucleophilic) to positive (electrophilic) locations on the molecule. In both the molecule the strong positive phase (dark blue region) appears on toluene and oxazole ring and strong negative phase around the nitrogen and oxygen atoms. Based on the GCRD and MESP parameters, it is obvious that the synthesised molecule has a broad energy band gap and good chemical stability, implying that these molecules might be used as an emissive layer in OLEDs.\\u003c/p\\u003e\\u003cp\\u003eBecause silver is the most often used contact electrode in OLEDs, fluorescence quenching of synthesised molecules was investigated using silver nanoparticles to better understand the electron transfer process.\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec11\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.5. Absorption Characteristics of Oxazole Derivatives in Ag nanoparticles:\\u003c/h2\\u003e \\u003cp\\u003eFigures\\u0026nbsp;\\u003cspan refid=\\\"Fig6\\\" class=\\\"InternalRef\\\"\\u003e10\\u003c/span\\u003e and \\u003cspan refid=\\\"Fig7\\\" class=\\\"InternalRef\\\"\\u003e11\\u003c/span\\u003e show the UV-vis absorption spectrum of OX-1 and OX-2 with silver nanoparticles. The absorption spectra of OX-1 and OX-2 in ethanol with and without silver nanoparticles. With different concentrations of silver nanoparticles, the absorption spectra of the oxazole derivatives were boosted and broadened without shift in the absorption maxima peak, as shown in Figs.\\u0026nbsp;\\u003cspan refid=\\\"Fig6\\\" class=\\\"InternalRef\\\"\\u003e10\\u003c/span\\u003e and \\u003cspan refid=\\\"Fig7\\\" class=\\\"InternalRef\\\"\\u003e11\\u003c/span\\u003e. This demonstrates that dyes interact with silver nanoparticles, resulting in the development of a ground state complex.\\u003c/p\\u003e \\u003cp\\u003eStern-Volmer (S-V) plots were generated using steady state techniques to elucidate the fluorescence quenching process between dyes and silver nanoparticles, as illustrated in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig9\\\" class=\\\"InternalRef\\\"\\u003e12\\u003c/span\\u003e.\\u003cdiv id=\\\"Equ1\\\" class=\\\"Equation\\\"\\u003e\\u003cdiv format=\\\"TEX\\\" class=\\\"mathdisplay\\\" id=\\\"FileID_Equ1\\\" name=\\\"EquationSource\\\"\\u003e\\n$$\\\\frac{{I}_{0}}{I}=1+{k}_{sv} Q$$\\u003c/div\\u003e\\u003cdiv class=\\\"EquationNumber\\\"\\u003e1\\u003c/div\\u003e\\u003c/div\\u003e\\u003c/p\\u003e \\u003cp\\u003eWhere, k\\u003csub\\u003eSV\\u003c/sub\\u003e are the steady-state Stern-Volmer quenching constants. The k\\u003csub\\u003eq\\u003c/sub\\u003e values represent the characteristics of the bimolecular quenching rate. The S-V plots using steady-state techniques are shown to be linear for all dyes, with high correlation coefficients (r) close to unity (see Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig11\\\" class=\\\"InternalRef\\\"\\u003e15\\u003c/span\\u003e). This strongly implies that the quenching is the result of dynamic or collisional quenching. Table-5 shows the slopes, intercepts, and correlation coefficients obtained from S-V plots. Table-5 shows that the values of the Stern-Volmer constants are in the same range as the previously published values [\\u003cspan citationid=\\\"CR28\\\" class=\\\"CitationRef\\\"\\u003e28\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eTable-5 shows the value of S-V constant (K\\u003csub\\u003esv\\u003c/sub\\u003e), bimolecular quenching constant (K\\u003csub\\u003eq\\u003c/sub\\u003e) and association constant (K\\u003csub\\u003es\\u003c/sub\\u003e)\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabk\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"9\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" 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 \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c9\\\" colnum=\\\"9\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eSample\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"4\\\" nameend=\\\"c5\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003eS-V plot\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"4\\\" nameend=\\\"c9\\\" namest=\\\"c6\\\"\\u003e \\u003cp\\u003eB-H plot\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eτ\\u003csub\\u003e0\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003e(ns)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003ek\\u003csub\\u003esv\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003ex10\\u003csup\\u003e5\\u003c/sup\\u003e M\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eK\\u003csub\\u003eq\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003ex10\\u003csup\\u003e14\\u003c/sup\\u003eM\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003es\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003er\\u003csup\\u003e2\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eSlope\\u003c/p\\u003e \\u003cp\\u003ex10\\u003csup\\u003e\\u0026minus;\\u0026thinsp;10\\u003c/sup\\u003eM\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eIntercept\\u003c/p\\u003e \\u003cp\\u003ex10\\u003csup\\u003e\\u0026minus;\\u0026thinsp;4\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003er\\u003csup\\u003e2\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003eK\\u003csub\\u003es\\u003c/sub\\u003e\\u003c/p\\u003e \\u003cp\\u003ex10\\u003csup\\u003e6\\u003c/sup\\u003e M\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003e\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eOX-1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1.32\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1.292\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.978\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.987\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e9.619\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.164\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.984\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e0.001\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eOX-2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1.45\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2.421\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1.644\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.933\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e10.984\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e21.646\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.999\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c9\\\"\\u003e \\u003cp\\u003e1.974\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec12\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.6. Binding mode studies\\u003c/h2\\u003e \\u003cp\\u003eUsing the Benesi\\u0026ndash;Hilderbrand [30] equation stoichiometry and the binding or association constant (KS) of the solute with silver nanoparticles are estimated from the following equation,\\u003cdiv id=\\\"Equ2\\\" class=\\\"Equation\\\"\\u003e\\u003cdiv format=\\\"TEX\\\" class=\\\"mathdisplay\\\" id=\\\"FileID_Equ2\\\" name=\\\"EquationSource\\\"\\u003e\\n$$\\\\frac{1}{{I}_{0}-I}=\\\\frac{1}{{K}_{s}\\\\left[C\\\\right]Q}+\\\\frac{1}{\\\\left[C\\\\right]}$$\\u003c/div\\u003e\\u003cdiv class=\\\"EquationNumber\\\"\\u003e2\\u003c/div\\u003e\\u003c/div\\u003e\\u003c/p\\u003e \\u003cp\\u003eIn this equation, I and I\\u003csub\\u003e0\\u003c/sub\\u003e represent the fluorescence intensity of a solute with and without silver nanoparticles, respectively. Where Ks, [C], and Q denote the association constant, dye concentration, and nanoparticle concentration, respectively. Figure\\u0026nbsp;\\u003cspan refid=\\\"Fig11\\\" class=\\\"InternalRef\\\"\\u003e15\\u003c/span\\u003e depicts 1/Q Vs 1/(I-I0) graphs for all dye-silver nanoparticles systems. Because all the charts are precisely linear, they give proof of 1:1 stoichiometry. The association constant (KS) is computed as the ratio of intercept to slope, and the values are shown in Table-5. The findings show that the synthesised molecule has a high affinity for silver nanoparticles.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec13\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.7. Role of Energy Transfer in Fluorescence Quenching\\u003c/h2\\u003e \\u003cp\\u003eThe spectral overlap between the nanoparticle absorption and dye emission spectra suggests the possibility of energy transfer. Forster's non-radiative energy transfer hypothesis explains the function of energy transfer in the fluorescence quenching of dyes by silver nanoparticles. Energy transfer occurs under the following circumstances, according to this theory: (a) the donor may produce fluorescence, (b) the emission spectrum of the donor and the absorption spectrum of the acceptor have greater overlap, and (c) the distance between the donor and the acceptor is less than 70 [\\u003cspan citationid=\\\"CR30\\\" class=\\\"CitationRef\\\"\\u003e31\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eFigure\\u0026nbsp;\\u003cspan refid=\\\"Fig12\\\" class=\\\"InternalRef\\\"\\u003e16\\u003c/span\\u003e depicts the overlap of the absorption spectrum of silver nanoparticles with the emission spectra of OX-1 and OX-2. As a result, energy transmission between dye molecules and silver nanoparticles is possible. Forster Eq.\\u0026nbsp;\\u003cspan refid=\\\"Equ3\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e [\\u003cspan citationid=\\\"CR30\\\" class=\\\"CitationRef\\\"\\u003e31\\u003c/span\\u003e] gives the critical energy transfer distance in angstroms when the energy transfer efficiency is 50% (R\\u003csub\\u003e0\\u003c/sub\\u003e).\\u003c/p\\u003e\\u003cp\\u003e\\u003cimg src=\\\"data:image/png;base64,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\\\" width=\\\"612\\\" height=\\\"40\\\"\\u003e\\u003cbr\\u003e\\u003c/p\\u003e \\u003cp\\u003ewhere k\\u003csup\\u003e2\\u003c/sup\\u003e (2/3) is the orientation factor relating the geometry of donor\\u0026ndash;acceptor dipoles, n (=\\u0026thinsp;1.33) is the refractive index of methanol, \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\phi }_{0}\\\\)\\u003c/span\\u003e\\u003c/span\\u003e is the fluorescence quantum yield of oxazole dye (OX-1\\u0026thinsp;=\\u0026thinsp;0.53 and OX-2\\u0026thinsp;=\\u0026thinsp;0.58) and J is the overlap integral between donor emission and acceptor absorption. The values of J can be calculated using Eq.\\u0026nbsp;(\\u003cspan refid=\\\"Equ4\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e) [\\u003cspan citationid=\\\"CR30\\\" class=\\\"CitationRef\\\"\\u003e31\\u003c/span\\u003e]:\\u003cdiv id=\\\"Equ4\\\" class=\\\"Equation\\\"\\u003e\\u003cdiv format=\\\"TEX\\\" class=\\\"mathdisplay\\\" id=\\\"FileID_Equ4\\\" name=\\\"EquationSource\\\"\\u003e\\n$$J={\\\\int }_{0}^{\\\\infty }{F}_{d}\\\\left(\\\\lambda \\\\right){\\\\epsilon }_{d}\\\\left(\\\\lambda \\\\right){\\\\lambda }^{4}d\\\\lambda$$\\u003c/div\\u003e\\u003cdiv class=\\\"EquationNumber\\\"\\u003e4\\u003c/div\\u003e\\u003c/div\\u003e\\u003c/p\\u003e \\u003cp\\u003ewhere \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({F}_{d}\\\\left(\\\\lambda \\\\right)\\\\)\\u003c/span\\u003e\\u003c/span\\u003e is the fluorescence intensity of the donor in the wavelength range to d, with total intensity normalized to unity, and \\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({\\\\epsilon }_{d}\\\\left(\\\\lambda \\\\right)\\\\)\\u003c/span\\u003e\\u003c/span\\u003e is the acceptor's extinction co-efficient at λ. Table-6 shows the values of the oxazole's overlap integral value. The integral value of the crucial transfer distance is determined using the value overlap and is found to be 28.142 \\u0026Aring; and 34.985 \\u0026Aring; for OX-1 and OX-2, respectively and are shown in Table-6. The findings show that fluorescence quenching is also caused by nonradiative energy transfer from the dye to the silver nanoparticles.\\u003c/p\\u003e \\u003cp\\u003eTable-6 the value of overlap integral and critical transfer distance\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"No\\\" id=\\\"Tabl\\\" border=\\\"1\\\"\\u003e \\u003ccolgroup cols=\\\"3\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSample\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eJ (M\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003ecm\\u003csup\\u003e\\u0026minus;\\u0026thinsp;1\\u003c/sup\\u003enm\\u003csup\\u003e4\\u003c/sup\\u003e)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eR\\u003csub\\u003e0\\u003c/sub\\u003e (\\u0026Aring;)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eOX-1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e7.331\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e28.142\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eOX-2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e9.812\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e34.985\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"4. Conclusions\",\"content\":\"\\u003cp\\u003eThe photophysical characteristics of the new oxazole derivatives OX-1 and OX-2 were investigated utilizing experimental and theoretical approaches. The ground and excited state dipole moments were empirically obtained using the Lippert\\u0026rsquo;s, Bakhshiev's, KawskiChamma- Viallet's, and solvent polarity equations and result suggest that synthesised molecules are more polar in excited sate than ground state. The ground state dipole moments, HOMO-LUMO, and molecule electrostatic potential map were also computed using \\u003cem\\u003eab initio\\u003c/em\\u003e calculations. Furthermore, spectroscopic interactions between newly synthesised dyes (OX-1 and OX-2) and freshly synthesised silver nanoparticles (size 40 nm) were studied. Increased absorbance and widening of absorption spectra for both dyes in the presence of varied quantities of silver nanoparticles show the potential of dye-nanoparticle interactions. Fluorescence quenching has been detected for both dyes in the presence of colloidal silver nanoparticles, indicating dynamic quenching, and a significant overlap between the absorption and emission spectra of the silver nanoparticle reveals that fluorescence quenching is also due to energy transfer.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eEthical Approval\\u003c/strong\\u003e: Not applicable \\u003c/p\\u003e\\n\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting interests\\u003c/strong\\u003e: Declared competing interest \\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors\\u0026apos; contributions\\u003c/strong\\u003e: \\u003c/p\\u003e\\n\\u003cp\\u003eSantosh R Mannopantar :Conceptualization; Data curation; Formal analysis; Investigation; Methodology; Resources; Software; Supervision; Validation; Visualization; Roles/Writing - original draft; Writing - review \\u0026amp; editing.\\u003c/p\\u003e\\n\\u003cp\\u003eV. S. Patil : Data curation; Formal analysis; \\u003c/p\\u003e\\n\\u003cp\\u003eM N Kalasad : Visualization; Roles/Writing - original draft; Writing - review \\u0026amp;editing.\\u003c/p\\u003e\\n\\u003cp\\u003ePavan Prabhala : Formal analysis; Investigation; Methodology; Resources\\u003c/p\\u003e\\n\\u003cp\\u003eA. S. Lalasangi : Data curation; Formal analysis;\\u003c/p\\u003e\\n\\u003cp\\u003eV. K. Kulkarni : Conceptualization; Data curation; Formal analysis; \\u003c/p\\u003e\\n\\u003cp\\u003eInvestigation; Methodology; Resources; Software; \\u003c/p\\u003e\\n\\u003cp\\u003eSupervision; Validation; Visualization; \\u003c/p\\u003e\\n\\u003cp\\u003eRoles/Writing - original draft; Writing - review \\u0026amp; editing. \\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding: Not applicable \\u003c/strong\\u003e\\u003c/p\\u003e\\n\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and materials\\u003c/strong\\u003e: All data can be accessed.\\u003c/p\\u003e\\n\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003eChen, Y., \\u0026amp; Shi, J. (2016). Chemistry of mesoporous organosilica in nanotechnology: molecularly organic\\u0026ndash;inorganic hybridization into frameworks. Advanced Materials, 28(17), 3235-3272.\\u003c/li\\u003e\\n\\u003cli\\u003eChen, G., Qian, Y., Zhang, H., Ullah, A., He, X., Zhou, Z., ... \\u0026amp; Shen, J. (2021). Advances in cancer theranostics using organic-inorganic hybrid nanotechnology. Applied Materials Today, 23, 101003.\\u003c/li\\u003e\\n\\u003cli\\u003eYao, H. B., Gao, M. R., \\u0026amp; Yu, S. H. (2010). Small organic molecule templating synthesis of organic\\u0026ndash;inorganic hybrid materials: their nanostructures and properties. Nanoscale, 2(3), 322-334.\\u003c/li\\u003e\\n\\u003cli\\u003ePark, W., Shin, H., Choi, B., Rhim, W. K., Na, K., \\u0026amp; Han, D. K. (2020). Advanced hybrid nanomaterials for biomedical applications. Progress in Materials Science, 114, 100686.\\u003c/li\\u003e\\n\\u003cli\\u003eGellé, A., Jin, T., de la Garza, L., Price, G. D., Besteiro, L. V., \\u0026amp; Moores, A. (2019). Applications of plasmon-enhanced nanocatalysis to organic transformations. Chemical reviews, 120(2), 986-1041.\\u003c/li\\u003e\\n\\u003cli\\u003eGell\\u0026eacute;, A. M. F. (2021). Shining Light on Plasmonic Silver Nanoparticles for For Catalysis (Doctoral dissertation, McGill University (Canada)).\\u003c/li\\u003e\\n\\u003cli\\u003eLiang, C., Lu, Z. A., Wu, J., Chen, M. X., Zhang, Y., Zhang, B., ... \\u0026amp; Xu, P. (2020). Recent advances in plasmon-promoted organic transformations using silver-based catalysts. ACS Applied Materials \\u0026amp; Interfaces, 12(49), 54266-54284.\\u003c/li\\u003e\\n\\u003cli\\u003eSindram, J., Volk, K., Mulvaney, P., \\u0026amp; Karg, M. (2019). Silver nanoparticle gradient arrays: Fluorescence enhancement of organic dyes. Langmuir, 35(26), 8776-8783.\\u003c/li\\u003e\\n\\u003cli\\u003eManuel, A. P., Kirkey, A., Mahdi, N., \\u0026amp; Shankar, K. (2019). Plexcitonics\\u0026ndash;fundamental principles and optoelectronic applications. Journal of Materials Chemistry C, 7(7), 1821-1853.\\u003c/li\\u003e\\n\\u003cli\\u003eZhang, H. Z., Zhao, Z. L., \\u0026amp; Zhou, C. H. (2018). Recent advance in oxazole-based medicinal chemistry. European journal of medicinal chemistry, 144, 444-492.\\u003c/li\\u003e\\n\\u003cli\\u003eAyati, A., Emami, S., Moghimi, S., \\u0026amp; Foroumadi, A. (2019). Thiazole in the targeted anticancer drug discovery. Future Medicinal Chemistry, 11(16), 1929-1952.\\u003c/li\\u003e\\n\\u003cli\\u003eGuerrero-Pepinosa, N. Y., Cardona-Trujillo, M. C., Garzon-Castano, S. C., Veloza, L. A., \\u0026amp; Sep\\u0026uacute;lveda-Arias, J. C. (2021). Antiproliferative activity of thiazole and oxazole derivatives: A systematic review of in vitro and in vivo studies. Biomedicine \\u0026amp; Pharmacotherapy, 138, 111495.\\u003c/li\\u003e\\n\\u003cli\\u003eAl-Kuraishy, H. M., Al-Gareeb, A. I., Elekhnawy, E., \\u0026amp; Batiha, G. E. S. (2022). Nitazoxanide and COVID-19: a review. Molecular biology reports, 1-8.\\u003c/li\\u003e\\n\\u003cli\\u003eYan, Z., Liu, A., Ou, Y., Li, J., Yi, H., Zhang, N., ... \\u0026amp; Hu, A. (2019). Design, synthesis and fungicidal activity evaluation of novel pyrimidinamine derivatives containing phenyl-thiazole/oxazole moiety. Bioorganic \\u0026amp; medicinal chemistry, 27(15), 3218-3228.\\u003c/li\\u003e\\n\\u003cli\\u003ePrabhala, P., Sutar, S. M., Manjunatha, M. R., Pawashe, G. M., Gupta, V. K., Naik, L., \\u0026amp; Kalkhambkar, R. G. (2022). Synthesis, In vitro and theoretical studies on newly synthesized deep blue emitting 4-(p-methylphenylsulfonyl-5-aryl/alkyl) oxazole analogues for biological and optoelectronic applications. Journal of Molecular Liquids, 119520.\\u003c/li\\u003e\\n\\u003cli\\u003eM.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman, G. Scalmani, V. Barone, B. Mennucci, G.A. Petersson, H. Nakatsuji, M. Caricato, X. Li, H.P. Hratchian, A.F. Izmaylov, J. Bloino, G. Zheng, J.L. Sonnenberg, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa, M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, T. Vreven, J.A. Montgomery Jr., J.E. Peralta, F. Ogliaro, M. Bearpark, J.J. Heyd, E. Brothers, K.N. Kudin, V.N. Staroverov, T. Keith, R. Kobayashi, J. Normand, K. Raghavachari, A. Rendell, J.C. Burant, S.S. Iyengar, J. Tomasi, M. Cossi, N. Rega, J.M. Millam, M. Klene, J.E. Knox, J.B. Cross, V. Bakken, C. Adamo, J. Jaramillo, R. Gomperts, R.E. Stratmann, O. Yazyev, A.J. Austin, R. Cammi, C. Pomelli, J.W. Ochterski, R.L. Martin, K. Morokuma, V.G. Zakrzewski, G.A. Voth, P. Salvador, J.J. Dannenberg, S. Dapprich, A.D. Daniels, O. Farkas, J.B. Foresman, J.V. Ortiz, J. Cioslowski, D.J. Fox, Gaussian-09, Revision B.01, Gaussian, Inc, Wallingford, CT, 2010\\u003c/li\\u003e\\n\\u003cli\\u003eNaik, L., Maridevarmath, C. V., Khazi, I. A. M., \\u0026amp; Malimath, G. H. (2019). Photophysical and computational studies on optoelectronically active thiophene substituted 1, 3, 4-oxadiazole derivatives. \\u003cem\\u003eJournal of Photochemistry and Photobiology A: Chemistry\\u003c/em\\u003e, \\u003cem\\u003e368\\u003c/em\\u003e, 200-209.\\u003c/li\\u003e\\n\\u003cli\\u003eE.Z. Lippert, Spektroskopische bestimmung des dipolmomentes aromatischer verbindungen im ersten angeregten singulettzustand, Z. Elektrochem., 61 (1957) 962-975. \\u003c/li\\u003e\\n\\u003cli\\u003eN. Mataga, Y. Kaifu, M. Koizumi, Solvent effects upon fluorescence spectra and the dipole moments of excited molecules, Bull. Chem. Soc. Jpn., 29 (1956) 465-470. \\u003c/li\\u003e\\n\\u003cli\\u003eN.G. Bakhshiev, N.G. Bakhshiev, Universal intermolecular interactions and their effect on the position of the electronic spectra of molecules in 2-component solutions, Opt. Spectrosc., 16 (1964) 821-832. \\u003c/li\\u003e\\n\\u003cli\\u003eA. Kawski, On the estimation of excited state dipole moments from solvatochromic shifts of absorption and fluorescence spectra, Z. Naturforsch., 57A (2002) 255-262. \\u003c/li\\u003e\\n\\u003cli\\u003eC. Reichardt, Solvatochromic dyes as solvent polarity indicators, Chem. Rev., 94 (1994) 2319-2358. \\u003c/li\\u003e\\n\\u003cli\\u003eY.G. Sidir, I. Sidir, Solvent effect on the absorption and fluorescence spectra of 7-acetoxy-6-(2,3-dibromopropyl)-4,8-dimethylcoumarin: Determination of ground and excited state dipole moments, Spectrochim. Acta A Mol. Biomol. Spectrosc., 102 (2013) 286-296. \\u003c/li\\u003e\\n\\u003cli\\u003eM. B. Smith, J. March, Advanced organic chemistry: reactions, mechanisms and structure, 6th ed. Wiley New York. 2012.\\u003c/li\\u003e\\n\\u003cli\\u003eR. G. Parr, W. Yang, Density Functional Theory of Atoms and Molecules, Oxford University Press, New York, 1989.\\u003c/li\\u003e\\n\\u003cli\\u003eV. K. Choudhary, A. K. Bhatt, D. Dash, N. Sharma, DFT calculations on molecular structures, HOMO\\u0026ndash;LUMO study, reactivity descriptors and spectral analyses of newly synthesized diorganotin (IV) 2-chloridophenylacetohydroxamate complexes, J. Comp. chem., 40, 27(2019) 2354-2363.\\u003c/li\\u003e\\n\\u003cli\\u003eL. R. Domingo, M. Guti\\u0026eacute;rrez, P. P\\u0026eacute;rez, Applications of the conceptual density functional theory indices to organic chemistry reactivity, Molecules, 21 (2016) 748.\\u003c/li\\u003e\\n\\u003cli\\u003eNaik, L., Khazi, I. A. M., \\u0026amp; Malimath, G. H. (2018). Turn-off fluorescence studies of novel thiophene substituted 1, 3, 4-oxadiazoles for aniline sensing. Sensors and Actuators A: Physical, 284, 145-157.\\u003c/li\\u003e\\n\\u003cli\\u003eNaik, L., Khazi, I. A. M., \\u0026amp; Malimath, G. H. (2020). Electronic excitation energy transfer studies in binary mixtures of novel optoelectronically active 1, 3, 4-oxadiazoles and coumarin derivatives. Chemical Physics Letters, 749, 137453.\\u003c/li\\u003e\\n\\u003cli\\u003eM.L. Benesi and J.H. Hildebrand, A Spectrophotometric Investigation of the Interaction\\u003cbr\\u003eof Iodine with Aromatic Hydrocarbons, J. Am. Chem. Soc. 71 (1949) 2703\\u003c/li\\u003e\\n\\u003cli\\u003eR. L. Joseph, Principles of Fluorescence Spectroscopy, 3rd ed., Springer, New York, 2006\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"journal-of-fluorescence\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"jofl\",\"sideBox\":\"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)\",\"snPcode\":\"10895\",\"submissionUrl\":\"https://submission.nature.com/new-submission/10895/3\",\"title\":\"Journal of Fluorescence\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false},\"keywords\":\"Fluorescence quenching, HOMO-LUMO, MESP, Ag, nanoparticles, Oxazole derivatives\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-2951736/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-2951736/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003eIn this study, the photophysical properties of oxazole derivatives such as 5-(furan-2-yl) -4-tosyloxazole (OX-1) and 5-(2-bromothiazol-4-yl)-4-tosyloxazoles (OX-2) were investigated using theoretical and experimental techniques. The ground and excited state dipole moments were empirically obtained utilising the solvatochromic shift technique and several solvatochromic correlations such as Lippert's, Bakhshiev's, KawskiChamma- Viallet's, and solvent polarity equations. The ground state dipole moments, HOMO-LUMO and molecule electrostatic potential map were also computed using ab initio calculations and evaluated using Gaussian 09 W software. Furthermore, spectroscopic interactions between newly synthesised dyes (OX-1 and OX-2) and freshly synthesised silver nanoparticles (size 40 nm) were studied. Increased absorbance and widening of absorption spectra for both dyes in the presence of varied quantities of silver nanoparticles show the potential of dye-nanoparticle interactions. Fluorescence quenching has been detected for both dyes in the presence of colloidal silver nanoparticles, indicating dynamic quenching, and a significant overlap between the absorption and emission spectra of the silver nanoparticle reveals that fluorescence quenching is also due to energy transfer.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e\",\"manuscriptTitle\":\"Systematic Photophysical Interaction Studies Between Newly Synthesised Oxazole Derivatives and Silver Nanoparticles: Experimental and DFT Approach\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2023-05-24 15:32:52\",\"doi\":\"10.21203/rs.3.rs-2951736/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Major revision\",\"date\":\"2023-06-20T12:09:40+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2023-06-18T16:19:31+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"e0871748-25c1-4585-9bee-c351a5c4f213\",\"date\":\"2023-06-14T02:10:40+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"f1089e42-84eb-418c-ad57-4f3f3cfe45bd\",\"date\":\"2023-05-25T11:37:17+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"906888ed-c5cc-4c16-a0cc-51a7b5e1e97d\",\"date\":\"2023-05-25T11:10:16+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2023-05-25T11:00:15+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2023-05-23T10:46:52+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2023-05-23T05:45:14+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Journal of Fluorescence\",\"date\":\"2023-05-18T10:25:14+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"journal-of-fluorescence\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"jofl\",\"sideBox\":\"Learn more about [Journal of Fluorescence](https://www.springer.com/journal/10895)\",\"snPcode\":\"10895\",\"submissionUrl\":\"https://submission.nature.com/new-submission/10895/3\",\"title\":\"Journal of Fluorescence\",\"twitterHandle\":\"\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"Springer Hybrid\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":false}}],\"origin\":\"\",\"ownerIdentity\":\"d644a9cf-dd42-4390-b987-1d32bb307041\",\"owner\":[],\"postedDate\":\"May 24th, 2023\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2023-10-16T22:13:20+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-2951736\",\"link\":\"https://doi.org/10.1007/s10895-023-03369-y\",\"journal\":{\"identity\":\"journal-of-fluorescence\",\"isVorOnly\":false,\"title\":\"Journal of Fluorescence\"},\"publishedOn\":\"2023-08-17 22:00:24\",\"publishedOnDateReadable\":\"August 17th, 2023\"},\"versionCreatedAt\":\"2023-05-24 15:32:52\",\"video\":\"\",\"vorDoi\":\"10.1007/s10895-023-03369-y\",\"vorDoiUrl\":\"https://doi.org/10.1007/s10895-023-03369-y\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-2951736\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-2951736\",\"identity\":\"rs-2951736\",\"version\":[\"v1\"]},\"buildId\":\"7rjqhiLT3MXkJMwkYKINL\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}