Thermodynamics of Solvation of Silver(I) Ion in Nonaqueous Solvents

The Gibbs energies of the transfer of the silver(I) ion from methanol (MeOH) to dimethyl sulfoxide (DMSO) and from ethanol (EtOH) to N,N-dimethylformamide (DMF) were determined by potentio-metry. Our own and literature data on the thermodynamic characteristics of the transfer of Ag+ from alcohols (S1) to aprotic (S2) solvents were summarized and analyzed. It has been established that the replacement of amphoteric solvents with aprotic ones leads to significantly increased solvation of the silver(I) ion. The enthalpy contribution to the Gibbs energy of ion transfer in the case of the replacement (S1 → S2) is dominant. The strengthening of solvate complexes of Ag+ with solvent in the case of the replacement of S1 by S2 is caused mainly by an increase in the electron donor-acceptor (EDA) interactions due to a decrease in the acidity of solvents.