The reaction pathways for the solvation of Li+ and Cl– in formic acid have been investigated by means of CNDO/2 MO SCF calculations. The energetically most favoured pathways for these reactions have been determined. The method describes satisfactorily the complete reactions, for both of which a nearly simultaneous change is found in all geometric parameters within short distances between the ions and formic acid. For the cation, long range interaction is observed only with carbonyl oxygen, while at the equilibrium position, interaction also exists with carbon and CH hydrogen. The polarization of the hydrogen bond in the anionic solvate and its function in charge transfer are discussed in detail.