On the performance of UAMI-EW force field for water - monohydric alcohol mixtures

We explore the composition dependence of a wide set of properties of liquid water - monohydric alcohol mixtures by using the isobaric-isothermal molecular dynamics computer simulations. Namely, methanol, ethanol and 1-propanol alcohols are considered. The recently proposed united atom, non-polarizable force field for each of alcohols, García-Melgarejo et al. (2021) [10], combined with the TIP4P/ε water model is applied. Accuracy of the force field and resulting physics of behavior are discussed. The composition trends of density, excess mixing volume and apparent molar volumes are evaluated. On the other hand, the excess mixing enthalpy, partial molar enthalpies and the coefficient of isobaric thermal expansion are reported. In addition, the self-diffusion coefficients, static dielectric constant and surface tension are investigated. Peculiarities of mixing of species upon changes of alcohol mole fraction are elucidated. The changes in the microscopic structure are explored in terms of pair distribution functions, coordination numbers and of hydrogen bonds. The quality of simulation results is critically evaluated by their comparison with experimental data. Conclusions of the present modeling and necessary developments are commented. •Alcohol (methanol, ethanol, propanol) - water mixtures are examined.•The UAMI-EW force field for alcohols and TIP4P/ε for water are applied.•Accurate description of mixing properties is confirmed.•Thermodynamic properties are discussed together with microscopic structure.