Fermi contact interaction and spin density distribution in the Mn² ion: an X_α study using theoretical exchange parameters

Abstract

The Fermi contact interaction and spin density distribution in the Mn⁺² ion were studied by a spin-polarized X_α calculation, using theoretical and empirical exchange parameters α. Theoretical α values, α_t, with different α for different spin, where α_t↑ < α_t↓, are necessary to predict Fermi contact terms and spin density distributions of the correct sign and magnitude; the Latter correction to the X_α potential did not improve the fit with the Hartree-Fock and experimental values.