First Principles Calculation for the Magnetic Structure of γ-Mn

Abstract

Magnetic structure of γ -Mn which is experimentally believed to be a collinear antiferromagnet with lattice distortion of c/a < 1 is investigated by taking the non-collinear spin structures into account in the LMTO-ASA. Comparison of the total energies for various magnetic structures indicates that at c/a=1 the non-collinear antiferromagnetic structure is more stable than the collinear structure, although the energy difference is quite subtle (less than 0.1, mRy/atom). It is shown that the lattice distortion to c/a < 1 is strongly responsible for the collinear antiferromagnetic structure and it simultaneously makes the system stable.