- Nick Weadock, The California Institute of Technology, Pasadena
The high solubility and diffusivity of hydrogen in hydride-forming metals provide an excellent platform for fundamental studies of phase transformations and kinetics. The speaker will discuss an experimental analysis of hysteresis in bulk and nanocrystalline PdH, specifically, the energetic contributions to hysteresis and subsequent effects on the phase transformation and chemical and coherent spinodals. The speaker will also present recent results of pressure-dependent quasielastic neutron scattering, a new technique that can be used to measure activation volume for hydrogen diffusion. Adiabatic diffusive jumps in YFe2H2.6 were found to occur with a small, positive activation volume of about 2 Å.