Fermi-Lowdin orbital self-interaction correction on magnetic properties of Cu(II)-acetate monohydrate*

We study the magnetic properties of copper acetate monohydrate [Cu(CH3COO)₂(H₂O)]₂ using the Fermi-Lowdin orbital based self-interaction corrected (FLOSIC) density functional method. Most common density functional approximations that often accurately predict equilibrium properties have a self-interaction error that tends to unphysically lower the energies of fractionally occupied state which leads to deviation from piecewise linear behavior of total energy between two integer occupations. This leads to delocalization of the orbitals which is more apparent in d-electron systems resulting in incorrect electron densities. We find that removing self-interaction error using FLOSIC improves the magnetic coupling constant resulting in better agreement with experiment. The performance of self-interaction corrected density functional approximations on the magnetic properties is studied. The effect of self-interaction correction on the orbitals, density and the zero field splitting parameters will be presented and discussed.