Temperature dependence of the mean square relative displacements of nearest-neighbour atoms derived from EXAFS spectra

Abstract

An investigation of the dependence on temperature of the extended X-ray absorption fine structure (EXAFS) above the K-edges of Cu and Co in the metals and above the K-edges of Rb and Sr in the compounds RbCl, SrS, SrF2 and SrCl2 has been performed. For Cu, Co, RbCl and SrS, the values of the correlated mean square relative displacements of nearest-neighbour atoms derived from EXAFS spectra show a good agreement with those calculated from a Debye model. The experimental data obtained are also compared with available data for mean square displacements of the individual atoms calculated from more-refined lattice vibrational models and with Debye-Waller factors used in X-ray diffraction experiments.

EXAFS Investigations of the Local Thermal Properties of Solids

“…Correlated Debye model. For monatomic Bravais crystals, the parallel MSRD can be described by an approximate correlated Debye Model [1,35,36] …”

Temperature-dependent transmission extended electron energy-loss fine structure of aluminum

“…1 However, exposing a silicon surface to CF 4 /H 2 is known to introduce hydrogen into the silicon crystal. 2 • 3 Hydrogen interacts with acceptors in siiicon forming pairs, e.g., the boron-hydrogen pairs, which are electrically inactive:~· 5 More complex defects related to hydrogen have also been reported,6·7 e.g., heavily damaged regions and {111} and {100}…”

An improved EXAFS-function calculation procedure for materials with small interatomic separation

“…Owing to its relative simplicity, the second of the methods (ii) is widely used, especially when only the knowledge of Rj is desired. Additional information concerning differences in bond lengths (Martens, Rabe, Schwentner & Werner, 1977, 1978Rabe, Tolkiehn & Werner, 1979c), mean-square relative displacements of nearest neighbours (B6hmer & Rabe, 1979;Rabe, Tolkiehn & Werner, 1979a;Stern et al, 1980) and backscattering amplitudes (Rabe etal., 1979b) is derived in a further stage from the transformation of limited ranges of F(r) back into k space.…”