**9. Conclusions**

MD simulations of the electrolyte solutions improve the understanding of a nature of the solvation in methanol-water mixtures. Despite very similar interactions of the ions with both solvent components the compositions of the ion shells and the bulk solvent may be different. This leads to the conclusion that the solvation of ions does not depend only on the ionsolvent interactions, but it is affected by the interactions between the solvent molecules. Particularly in highly associated solvents a strong tendency to prevent the H-bonded network of the solvent competes with the ion-solvent interactions and it may lead to a selective solvation of the ions.

The H-bonds between the H-donor water and H-acceptor methanol molecules are energetically favourable. The molecules in the cationic shells exhibit the antidipole orientation, which favours the H-donor water molecules, whereas the almost linear H-bond

MD Simulation of the Ion Solvation in Methanol-Water Mixtures 423

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