Magnetism in bcc and fcc manganese

Density-functional theory is used to compute the ferromagnetic moment as a function of lattice constant for bcc and fcc Mn. For bcc Mn, a relatively small moment is found in the lattice-constant range 5.205.90 a.u., with a discontinuous low-spin to high-spin transition occurring somewhere in the double-moment region 5.90{~}7.275 a.u., with a discontinuous zero-moment to high-moment transition occurring near a=7.275 a.u. Information obtained from magnetic susceptibility calculations is used to predict the magnetic order of the ground state in some of the lattice-constant ranges considered. The susceptibility calculations indicate that bcc Mn has a ferromagnetic ground state in the range 5.26.8 a.u.