Breaching the Axial Limits in Ln(III) Single-Ion Magnets Using External Electric Field

Single-Molecule Magnets have potential applications in several nano-technology applications including in high-dense information storage devices and realization of this potential application lies in enhancing the barrier height for magnetization reversal (U eff ). Recent literature examples suggest that the maximum values that one can obtain using a ligand field are already accomplished. Here we have explored using a combination of DFT and ab initio CASSCF calculations, the way to enhance the barrier height using an oriented external electric field for top three Single-ion Magnets ([Dy(Py) 5 (O t Bu) 2 ] + ( 1 ) and [Er{N(SiMe 3 ) 2 } 3 Cl] - ( 2 ) and [Dy(Cp Me3 )Cl] ( 3 )). For the first time our study reveals that, for apt molecules, if appropriate direction and value of electric fields are chosen, the barrier height could be enhanced twice that of the limit set by the ligand field. This novel non-chemical-fine tuning approach to modulate the magnetic anisotropy is expected to yield new generation SIMs.