First-principles elastic constants and phonons of delta-Pu

Elastic constants and zone-boundary phonons of delta-plutonium have been calculated within the density-functional theory. The paramagnetic state of delta-Pu is modeled by disordered magnetism utilizing either the disordered local moment or the special quasirandom structure techniques. The anomalously soft C-' as well as a large anisotropy ratio (C-44/C-') of delta-Pu is reproduced by this theoretical model.

Also the recently measured phonons for delta-Pu compare relatively well with their theoretical counterpart at the zone boundaries.