Electronic structure and x-ray magnetic circular dichroism in the Mn3CuN perovskite

The electronic and magnetic structures of Mn3CuN are investigated theoretically from first principles using the fully relativistic Dirac LMTO band structure method. Mn3CuN possesses a magnetic phase transition at T-C = 143 K from a high temperature paramagnetic phase to a low temperature ferromagnetic one with a noncollinear magnetic structure. The transition is accompanied by a structural change from the cubic to the tetragonal lattice. In low temperature phase two Cu moments and two Mn moments (Mn-2 and Mn-3) ferromagnetically align along the c axis while other four Mn-1 magnetic moments are canted from the c axis to [111] direction by angle Theta = +/-76.2. The x-ray absorption spectra and x-ray magnetic circular dichroism (XMCD) spectra of Mn3CuN are investigated theoretically from first principles. The origin of the XMCD spectra in the Mn3CuN compound is examined. The calculated results are compared with the experimental data. (C) 2014 AIP Publishing LLC.