The effects of 5f localization on magnetic properties of NpSn 3

Abstract

The structural, electronic and magnetic properties of NpSn 3 have been calculated using density functional theory by WIEN2K package. The total energy calculations indicate that at zero pressure the anti-ferromagnetic phase is the most stable phase. The magnetic moment calculation within local density approximation (LDA) and generalized gradient approximation (GGA) approaches show that LDA and GGA are not good approaches for this compound. To improve the result, we have calculated the magnetic moment using LDA+ U approach. The comparison of total magnetic moment of NpSn 3 within LDA+ U approach with experimental value shows that the best Coulomb repulsion term for Np atom is achieved with U=2.5 eV and J=0.5 eV. The calculation of orbital and spin magnetic moment as a function of U has been performed. The calculation of orbital magnetic moment as a function of unit-cell volume within LDA+ U approach has been performed.