We develop a density functional approach for the phase behavior of the restricted primitive model for electrolyte solutions confined to slit-like pores. The theory permits to evaluate the effects of confinement on the ionic vapor -ionic liquid coexistence envelope. We have shown that due to confinement in pores with uncharged walls the critical temperature of the model decreases compared to the bulk. Also the coexistence envelope of the transition is narrower in comparison to the bulk model. The transition between dense and dilute phase represents capillary evaporation. We have analyzed changes of the density profiles of ions during transition. Possible extensions of this study are discussed.

We explore the effects of composition and temperature on the apparent molar volumes of species of water-methanol mixtures. Isothermal-isobaric molecular dynamics simulations are used with this purpose. Several combinations of models for water and for methanol are explored. Validity of predictions concerned with a puzzling minimum of apparent molar volume of methanol in water-rich solutions is tested against experimental results.

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Isothermal-isobaric molecular dynamics simulations are used to examine the microscopic structure and principal thermodynamic properties of a model solution consisting of NaCl salt dissolved in methanol solvent. Four united atom force fields for methanol are involved. Concerning ion solutes we used the Joung-Cheatham, Smith-Dang models as well as the model from the laboratory of Vrabec. Our principal focus is to evaluate the quality of predictions of different combinations of models for basic properties of these solutions. Specifically, we explored the change of density on molality, the structural properties in terms of various pair distribution functions, the coordination numbers, the number of ion pairs and the average number of hydrogen bonds. In addition, changes of the self-diffusion coefficients of species, the solvent dielectric constant and the evolution of the surface tension with ion concentration are described.

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