How to Build Molecules with Large Magnetic Anisotropy

The magnetic anisotropy of mononuclear transition-metal complexes has been studied by means of electronic Structure calculations based Oil density functional theory. The variation of the zero-field splitting (ZFS) parameters has been analyzed for the following characteristic distortions: a tetragonal Jahn-Teller distortion, the Bailar twist, the Berry pseudorotation, and the planarization of tetrahedral complexes. Finally the coupling of mononuclear building blocks in polynuclear complexes to obtain a large negative magnetic anisotropy necessary to improve their single-molecule-magnet (SMM) behavior has been studied.