Neutron diffraction study of the new hexagonal Laves phase (Hf,Ti)(Ni,V)(2) and its deuteride

A new hexagonal C14 Laves phase hydrogen storage alloy and its deuteride ha s been studied with neutron diffraction. The new Laves phase precipitated a s a second phase when a vanadium-based solid solution, TiV3Ni0.56, was allo yed with hafnium. From the structural refinements it was suggested that Hf is situated at the A site and Ni at the B sites. The Ti and V occupancy cou ld not be ascertained, but from structural consideration of related alloys, supported by EDS analysis, we suggest that they occupy the A and B site, r espectively. The deuterium atoms were located to mainly occupy one of the t etrahedral A(2)B(2) interstices, resulting in the formula unit (Hf,Ti)(Ni,V )(2) D-2. (C) 1999 Elsevier Science S.A. All rights reserved.