Binary collisions in fluids: I: single particle density correlation function

Abstract

Binary collision expansion is applied to the space-tinic memory function associated with the single particle density correlation function. Thc ilsc of the potential of mean force as the interaction potential in the determination of two particle dynamics, thus taking into account the structural corrclations of the fluid, is found to yield significantly improved results for thc correlation function. Comparison of oilr results with molccular dynamics and experimental values shows very good agrecmcnt over a wide range of densities and wave vectors.Un dcvcloppemcnt en tcrmes de collisions binaires cst applique la fonction dc mCmoirc spatio-tcmporellc associCe avec la fonction dc corrdlation dc dcnsitc unc seulc partieulc. On trouve quc I'utilisation du potcnticl de force moycnnc comme potenticl d'intcraction dans la determination de la dynamiquc i deux partieulcs, de faqon a tenir comptc dcs corrdlations structurales du tluiclc, donne tine amelioration notable dcs rCsultats pour la fonction dc corrdlation. La comparaison dc nos rcsultats avcc des calculs dc dynamique mol6eulaire ct Ics valeurs cxpdrimentales indique un accord excellent pour une gammc Ctendue de dcnsitis ct de veeteurs d'onde.[Traduit par Ic journal]Can. J. Phys 61. 926 (1983) i