THERMAL-DEPENDENCE OF MULTIPLE-SCATTERING USING INDEPENDENTLY ESTABLISHED DYNAMICAL INFORMATION

Thermal disorder in EXAFS is normally treated using adjustable paramet ers which assign Debye-Waller like terms to all of the single and mult iple scattering paths contributing to the fine structure. The resultin g calculation may well fit an incorrect theory to the data. This paper describes a study in which the multiple scattering theory is quantita tively tested by eliminating the fitting procedure and inputing predet ermined values for the thermal disorder in a configurational averaging calculation. The test system chosen is the zinc tetraimidazole comple x in which all 105 vibrational normal modes have been modelled and the ir effects on the EXAFS signal calculated as a function of temperature .