Charge state and diffusion of hydrogen in the TiZrNi icosahedral alloy

The electronic structure of a hydrogen atom in a 1/1 approximant of the Ti-Zr-Ni icosahedral quasicrystal is investigated using ab initio methods based on the density functional theory. The charge state of the hydrogen atom in Ti₃₆Zr₃₂Ni₁₃ with different types of tetrahedral pores, as well as the charge state of hydrogen at a ratio H/M ≈ 1.7, is determined. The hydrogen atom is found to be in a nearly neutral state. The coefficient of hydrogen diffusion in Ti₃₆Zr₃₂Ni₁₃ is calculated.