The Use of X-ray Absorption Spectra for Validation of Classical Force-Field Models

Extended X-ray absorption fine structure (EXAFS) spectroscopy and molecular dynamics (MD) simulations are two complementary techniques widely used to study the atomic structure of materials. Their combined use, known as the MD-EXAFS approach, allows one to access the structural information, encoded in EXAFS, far beyond the nearest coordination shells and to validate the accuracy of the interaction potential models. In this study we demonstrate the use of the MD-EXAFS method for a validation of several force-field models on an example of the cubic-perovskite SrTiO₃ and hexagonal wurtzite-type ZnO crystals.