Experimentally consistent atomistic modeling of bulk and local structure in liquids and disordered materials by empirical potential structure refinement

Abstract

This article presents an overview of the use of the empirical potential structure refinement (EPSR) technique for generating three-dimensional atomistic models of liquids and structurally disordered solids that are consistent with experimental neutron and X-ray scattering data. The extension of this technique through the calculation of extended X-ray absorption fine structure (EXAFS) spectra is outlined, and the benefits of this are demonstrated for a range of systems and in particular for our ability to address structural questions of importance in solution chemistry. The model systems chosen as examples for structural analysis are (i) liquid gallium, (ii) silica glass, and (iii) a 1 m aqueous solution of YCl3. The advantages of this analytical approach for addressing chemically specific structural questions in disordered systems are discussed within the context of the experimental alternatives based on the techniques of neutron scattering with isotopic substitution and anomalous X-ray scattering.