Magnetism in the strained ordered phases of PtxFe1-x, and PtxCo1-x (x=0.25, 0.5, and 0.75)

The response of the magnetic moment of the Llo and L1(2) ordered phases of PtxM1-x (M = Fe,Co) (x = 0.25, 0.5, and 0.75) to compressive and tensile strains have been investigated using density functional theory (DFT). The magnetic moment of the Pt0.75M0.25 and Pt0.50M0.50 phases varies linearly compared to the response of the Pt0.25M0.75 alloys which shows a transition in the rate of change of magnetic moment at approximately zero strain. For all phases the mechanism of magnetic moment change under strain is shown to be intra-orbital charge transfer within the Pt, Fe and Co d shells. The strained and equilibrium magnetic band structures of each phase contain spin-orbit effects which are presented and discussed.