Pressure and temperature dependence of CDWS and soft-mode behavior in. cap alpha. -U

Neutron scattering experiments have revealed soft mode behavior and the formation of two sets of extra reflections in the vicinity of 43 K, one nearly commensurate and one incommensurate with the underlying lattice of ..cap alpha..-U. The data suggest that the set of nearly commensurate reflections is the manifestation of scattering from discommensurations between the domains of the ICDW of the bulk crystal. More recent neutron scattering measurements under applied hydrostatic pressure have shown that the nearly commensurate and incommensurate reflections can be suppressed with about 2 to 3 kbar and 6 kbar, respectively. This suppression is thought to be related to the pressure dependence of superconductivity at low temperatures.