Extraction of atom-atom bridge and direct correlation functions from molecular simulations: A test for ambient water

We compute partial structure factors for SPC/E water under ambient conditions, using radial distribution functions derived from simulations and employing finite-size corrections. We calculate atom-atom direct correlation functions by an inverse solution to reference interaction site model integral equations with account of long-range asymptotics of the functions as additional constraints. We split the short- and long-range contributions to the direct functions in the Ewald type manner. Finally we reconstruct atom- atom bridge functions. The obtained direct correlation functions are compared with the data obtained by the hypernetted chain approximation. (C) 2013 Elsevier B.V. All rights reserved.