Open AccessEinstein and Debye models for EXAFS parallel and perpendicular mean‐square relative displacements
Author(s) -
Vaccari M.,
Fornasini P.
Publication year - 2006
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049506018504
Subject(s) - extended x ray absorption fine structure , debye , einstein , mean squared displacement , physics , square (algebra) , eigenvalues and eigenvectors , displacement (psychology) , atom (system on chip) , quantum mechanics , mathematics , absorption spectroscopy , geometry , molecular dynamics , computer science , psychology , psychotherapist , embedded system
The correlated Einstein and Debye models for EXAFS parallel mean‐square relative displacement (MSRD) are derived from the general expression in terms of eigenfrequencies and eigenvectors of the dynamical matrix, without ad hoc assumptions. The two models are generalized to parameterize also the EXAFS perpendicular MSRD. The physical meaning of Einstein frequencies, as well as the application of the Debye model to crystals with more than one atom per cell, are critically discussed.