Predicting Magnetic\nBarriers in Lanthanide Complexes\nwith Electrostatic Potential Charges

Single-molecule magnets (SMMs) with slow relaxation of\nmagnetization\nand blocking temperatures above that of liquid nitrogen are essential\nfor practical applications in high-density data storage devices and\nquantum computers. A rapid and accurate prediction of the effective\nmagnetic relaxation barrier (<i>U</i><sub>eff</sub>) is\nneeded to accelerate the discovery of high-performance SMMs. Using\ndensity functional theory and multireference calculations, we explored\ncorrelations between <i>U</i><sub>eff</sub>, partial atomic\ncharges, and the anisotropic barrier for a series of sandwich-type\nlanthanide complexes containing cyclooctatetraene, substituted cyclopentadiene,\nphospholyl, boratabenzene, or borane ligands. Our results show a correlation\nbetween the electrostatic potential charge of the lanthanide ion in\nthe complex and <i>U</i><sub>eff</sub>. Systematic ligand\nmodifications show that reducing ligand nucleophilicity and incorporating\nsoft bases enhance magnetic anisotropy and <i>U</i><sub>eff</sub> values. This work identifies a correlation to predict <i>U</i><sub>eff</sub> values and optimization of ligand coordination\nenvironments in lanthanide-based SMMs.