AB-INITIO STUDY OF INNER-SPHERE REORGANIZATION ENERGY FOR DIATOMIC-MOLECULES IN GAS-PHASE ELECTRON-TRANSFER PROCESSES

On the basis of the improved self-exchange model of reorganization phe nomenon and accurate potential functions, several scaling methods of i nner-sphere reorganization energy (RE) of diatomic molecules in gas-ph ase electron transfer processes are presented in this paper, the struc tural reorganization index is given, and the parameters involved are d etermined via ab initio calculation at the Hartree-Fock self-consisten t field level (HF-SCF/6-31G). The results indicate that ab initio res ults give good agreement with experiment for the inner-sphere RE and t he potential constants (r(e),D-e,f,g) of reactant molecules, and that the Hartree-Fock method is an accurate and reliable method for analyzi ng the reorganization effects in gas-phase electron transfer processes . The estimated errors for inner-sphere RE are within +/-500 cm(-1) (/-1.5 kcal mol(-1)) or less, and are due to the limited basis sets wit hin the HF-SCF method. It should be emphasized that, for gas-phase ele ctron transfer processes, it is essential to calculate accurately the inner-sphere RE, while the outer-sphere effect may be neglected.