New Theoretical Investigation on the Electronic Structure and Magnetic Interaction for Fluorides MnF2

The self-consistent ab initio calculations, based on density functional theory (DFT) approach and using full-potential linear augmented plane wave (FLAPW) method, are performed to investigate both electronic and magnetic properties of the MnF2 compounds. Polarized spin and spin-orbit coupling are included in calculations within the framework of the ferromagnetic state between two adjacent Mn atoms. Magnetic moment considered to lie along (001) axis is computed. The antiferromagnetic and ferromagnetic energies of MnF2 systems are calculated. Obtained data from ab initio calculations are used as input for the high-temperature series expansion calculations combined with the Pad, approximant to compute the N,el temperature and critical exponent. The exchange interactions between the magnetic atoms M-Mn in MnF2 are calculated using the mean field theory. The high-temperature series expansions of the magnetic susceptibility with the magnetic moments of Mn in MnF2(m (Mn)) are given.