Local structure in hydrogenated Ti-Zr-Ni quasicrystals and approximants

摘要

We have investigated the influence of hydrogen on the local structure of Ti-Zr-Ni alloys, icosahedral quasicrystals or crystalline approximants, using extended X-ray absorption fine structure (EXAFS). With an increasing hydrogen-to-metal ratio from 0 to 1.7, a general increase of all the mean first distances was found except for the Zr-Ni (Ni-Zr) ones. The perturbation of the (quasi)lattice, induced by hydrogenation, is a maximum around the Ti and Zr atoms, which suggests that hydrogen atoms sit preferentially near titanium and zirconium atoms.