Electronically Induced Phase Transformation.

A new technique for determining the electronic structure of bulk solids has been developed by solving Poisson's equation for a general charge density and potential. All contributions to the potential are completely taken into account in the Hamiltonian matrix elements. The high accuracy of this approach allows us to go beyond traditional treatments and to consider the total energy which allows the accurate determination of structural information (lattice parameters, force constants, etc.) and total energy determinations of the lowest energy phase. The problems treated during this period include: (i) excited state properties of rare-earths and their compounds, (ii) room temperature superconductivity in metallic hydrogen under high pressure and the nature of the molecular to metal phase transition in hydrogen under high pressure, (iii) total energy theory of mixed valence, (iv) electronic structure and superconductivity in the high Tc A15 compounds, and (v) superconductivity and magnetism of C15 intermetallic compounds.