X-Ray and Neutron Scattering Investigations of YCo3 — H*

Various structural studies of YCo^H(D)x in the (3-phase (0<x<2) are described, where hydrogenation induces a cyclic variation betweeen ferromagnetic and paramagnetic states. X-ray diffraction measurements determined that the expansion of the lattice is localised to components of the structure which are related to the Laves phase, YCo2Neutron diffraction and inelastic neutron scattering were also used in tandem, and hydrogen occupation of a single (36i) tetrahedral site was inferred for the entire concentration range.