Sub-nano and Nano-structures of Hydrides of LaNi 5 and its related Intermetallics

Sub-nano and nano-structures of intermetallics such as LaNi 5 and its related alloys were studied by in-situ X-ray and neutron diffraction methods. From the profile shape analysis, changes in lattice strain and crystalline size during hydrogenation/dehydrogenation were estimated, while the crystal (sub-nano) structures were refined by the Rietveld method using diffraction patterns. The crystallite size of the alloys studied did not change during hydrogenation and dehydrogenation. It was found formation of remarkably dense dislocations and vacancies in the lattice of hydrides of LaNi 5 and related intermetallics.