Material Technology

Diffusive hydrogen motion in ZrBe2H0.56: A quasielastic neutron scattering study

Cappelletti, R.L. , Udovic, T.J. , Chowdhuri, Z. , Hauback, B.C. , Maeland, A.J. , Dimeo, R.M.
Physica B: Condensed Matter, Vol. 385-386 I (27 November 2006), 208-211
Publ. year
Publ. type
In ZrBe2H0.56, Be planes are separated by hexagonal Zr planes in the AlB2 structure with the H atoms occupying interstitial sites that form a honeycomb net in the Zr planes. The data from quasielastic neutron scattering above 500 K using two spectrometers covering a wide range of resolutions from 1 to 64 μeV can be fitted with a simple model using only two parameters for all momentum transfers at each temperature. The parameters are an elastic-like fraction and the hopping rate of a quasielastic contribution consisting of two-dimensional nearest-neighbor uncorrelated hopping among the partially occupied interstitial sites. The temperature dependence of the hopping rate follows an Arrhenius relation with an activation energy of 0.30±0.02 eV.
Elsevier link