Magnetic structure of bcc and fcc manganese

Abstract

Self-consistent band-structure calculations are used to obtain the ferromagnetic moment as a function of lattice constant for bcc and fcc Mn. The ferromagnetic moment of bcc Mn is found to change discontinuously from a small to a large value as the lattice constant increases, while the fcc moment is found to change discontinuously from zero to a large value with increasing atomic volume. In the bcc case, the transition occurs inside a narrow double moment region in which the low spin and high spin states coexist. Information from magnetic susceptibility calculations on bcc and fcc Mn is used to predict whether the ground state is ferromagnetic or antiferromagnetic in certain ranges of lattice constant.