Noncollinear magnetism in substitutionally disordered face-centered-cubic FeMn

We use first principles electronic structure techniques to study the magnet ic structure of gamma-FeMn using the Korringa-Kohn-Rostocker multiple-scatt ering approach in conjunction with an extension of the single site coherent potential approximation to noncollinear magnetic structures. Our results s how that the noncollinear 3Q and 2Q structures are both stable solutions wi th the former being slightly lower in energy. The collinear solutions could only be converged in a traditional spin-polarized calculation and are unst able in a noncollinear treatment. (C) 1999 American Institute of Physics. [ S0021-8979(99)59008-7].