The Massively Parallel O[N] LSMS-Method: Alloy Energies and Non-Collinear Magnetism

Abstract

AbstractWe present an overview of the locally self-consistent multiple scattering (LSMS) method. The method is based on real space multiple scattering theory, is naturally highly parallel, and has been implemented on Intel Paragon parallel platforms within the Center for Computational Sciences at Oak Ridge National Laboratory. O(N)-scaling is demonstrated for unit cells as large as 1000-atoms. We discuss in detail how the real space convergence properties of the method can be controlled by taking advantage of the stationary properties of a finite temperature Harris-Foulkes free energy functional. We show how the LSMS method can be combined with spin-dynamics to treat non-collinear magnetic states of materials. We show some preliminary results for the ground state magnetic structure of FCC Fe0.6 5Ni 0.35 alloys that indicate the possible existence of non-collinear arranges of magnetic moments in this system.