Quasicrystalline Ti45Zr38Ni17Hx samples were prepared with hydrogen-to-meta
l ratios (H/M) ranging from 0.25 to 1.85. The higher-concentration samples
lost hydrogen, falling to H/M approximate to 1.6 over the course of days to
weeks. The calibration of x-ray peak shifts as a measure of H/M, previousl
y based on an extrapolation for H/M > 1.6, has been confirmed. Nuclear magn
etic resonance measurements of the second moments (M-2) of the dipole-broad
ened H-1 line show the dependence on H/M expected for uniform filling of th
e quasicrystal with hydrogen. M-2 data were also consistent with canonical
cell-tiling models of the host structure when hydrogen was sited preferenti
ally near Ti or Zr neighbors. The quasicrystalline structure allows the che
mical preference in hydrogen siting to be compatible with spatially uniform
filling of the quasicrystal.