ASSESSMENT OF THE VALIDITY OF INTERMOLECULAR POTENTIAL MODELS USED INMOLECULAR-DYNAMICS SIMULATIONS BY EXTENDED X-RAY-ABSORPTION FINE-STRUCTURE SPECTROSCOPY - A CASE-STUDY OF SR2+ IN METHANOL SOLUTION

Molecular dynamics simulations have been carried out for Sr2+ in metha nol using different Sr2+ Lennard-Jones parameters and methanol models. X-ray absorption fine structure. (EXAFS) spectroscopy has been employ ed to assess the reliability of the ion-ion and ion-methanol potential functions used in the simulations. Radial distribution functions of S r2+ in methanol have been. calculated for each simulation and compared with the EXAFS experimental data. This procedure has allowed the dete rminations of reliable Sr2+-methanol models which have been used in lo nger simulations providing an accurate description of the dynamic and structural properties of this system. (C) 1998 American Institute of P hysics.