Here we report these studies by a new computational method based on the dynamical mean field and the linear response theories. This method allows us to incorporate correlation effects between f-electrons, which are important for modeling arbitrary waves of atomic displacements. We compute phonon dispersion relations for the high-temperature phases and find an intrinsic instability of the bcc epsilon-Pu. By estimating the entropy associated with the phonon dynamics in delta and epsilon phases we explain the origin of the delta->epsilon transition as driven by phonon entropy.

The calculated phonon spectra provide an important insight on the vibrations of the Pu lattice.

(**In collaboration with X. Dai, G. Kotliar, A. Migliori, and E. Abrahams)