Computer simulation studies of the liquid mixtures water-dimethylsulfoxide using different effective potential models: Thermodynamic and transport properties

This work demonstrates the first part of the results obtained in the framework of our extensive molecular dynamics simulations (MDS) of binary mixtures of water with dimethylsulfoxide (H2O-DMSO). The present treatment has been devoted to the estimation of the ability of previously proposed potentials for pure liquid water and DMSO in predicting certain properties of the water-DMSO mixtures at ambient conditions. Three widespread effective potential models for water (SPC, SPCE, TIPS2), in combination with the P2 model of DMSO, were employed to simulate the mixtures at state points for which experimental data are available. The present simulations have revealed that the results obtained differ from model to model. Specifically, we found that among the three models used, the SPC/P2 model, and TIPS2/P2 to a lower extent, yields the most reasonable descriptions of the mixture. However, these models yield results of somewhat restricted accuracy compared to the experimental data. Therefore, a further modification of the potential parameters used seems to be needed to improve agreement between the simulated and experimental properties of the system over the entire range of compositions. (C) 2002 Elsevier Science B.V. All rights reserved.