SOME COMMENTS ON THE DEVELOPMENT OF THE THEORY OF PROTON TRANSFER IN SOLUTION

The bond stretching model and the solvation barrier model for proton transfer in solution and their relations to the author's work are considered. The essential results of that work are shown to be quite independent of any assumption about the relative role of the bond-stretching and the solvent reorganization in the proton transfer. Some misinterprations of the above treatment are discussed. In a recent paper of DOGONADZE and KUZNETSOy) two different approaches to the calculation of the probability of proton transfer in polar media have been compared. The first one, originating from the work of HORIUTI and POLANYIl, takes into account only for the stretching of the chemical bond A-H+ of a molecule AHz in a solution due to the chemical excitation of the vibrational states in the course of reaction. The other approach, used by DOGONADZE et al.,4), consideres the primary role of the solvent polarization which changes during the proton transfer process, according to an idea suggested first by LIBBI) and developed further by MARCUS), HUSH7), LEYICH and DOGONADZE) for election transfer processes. A similar comparison between the two approaches is also made in a paper of KRISTALIK, TSIONSKY and TITOYA). Surprisingly, in both papers, as well as in some earlier papers of the same authors), my work ,12) is quoted as a treatment of proton transfer reactions in which the role of the solvent is "entirely ignored" as in the bond-stretching model of HORIUTI-POLANYI) used by other authors13). This statement is, however, completely incorrect, which is easily seen if one reads more carefully my papers ,12). The choice of a model to describe a physical process depends largely on the purpose of investigation. The model may be adequate to reality in some respect and not adequate in an other respect. Thus, in 1935 HORIUTI * ) Institute of Physical Chemistry, Bulgarian Academy of Sciences, Sofia 13, Bulgaria.