Determination of two- and three-body correlation functions in ionic solutions by means of MD and EXAFS investigations.
0 ' ' • ' ' ' ' ' ~ The solvation structure of Sr 2+ ions in acetonitrile has been studied by x-ray absorption spectroscopy (XAS) and molecular dynamics (MD) simulations. The extended x-ray absorption fine structure (EXAFS) above the Sr K-edge has been interpreted in the framework of the multiple scattering (MS) formalism and, for the first time, clear evidence of MS contributions has been found for noncomplexing ions in solution. Molecular dynamics has been used to generate the partial pair 9(r) and the three-body 9(rl , r2, 0) distribution functions from which a model x(k) has been constructed. An excellent agreement has been found between the theoretical and experimental data. This result demonstrates the ability of the XAS technique in probing three-body correlation functions in solutions.