A study was made of H sites in the 1∕1 approximant structure of the icosahedral TiZrNi quasicrystal. A Rietveld refinement of neutron and X-ray diffraction data determined the locations of interstitial H atoms. Density-functional methods predicted the energy of H on all possible interstitial sites. Rietveld refinement showed that the H atoms were preferentially located in the 2 lowest-energy sites. Filling of the remaining H sites was dominated by repulsive H-H interactions at short distances.

Location and Energy of Interstitial Hydrogen in the 1∕1 Approximant W - TiZrNi of the Icosahedral TiZrNi Quasicrystal - Rietveld Refinement of X-Ray and Neutron Diffraction Data and Density-Functional Calculations. R.G.Hennig, E.H.Majzoub, K.F.Kelton: Physical Review B, 2006, 73[18], 184205 (6pp)