The orientation and distance-dependence analysis of the electron transfer reactivity: An electron correlation level investigation of Mn2+(H2O)2/Mn3+(H2O)2 system

Abstract

The structures, properties, and the electron transfer reactivities of Mn 2+ (H 2 O) 2 /Mn 3+ (H 2 O) 2 have been investigated in this article at the different levels of theory. The geometrical optimizations that have been made at the UMP2(full)/6-311+G * level for these two species, the binding characteristics, natural orbital analysis, and the electronic configurations, have been discussed at the UMP2(full)/6-311+G * optimized geometries. A novel description scheme is presented for the overall electron transfer rate and calibrated by the Mn 2+ (H 2 O) 2 /Mn 3+ (H 2 O) 2 pair. The relevant energy quantities are also calculated at different levels of theory including MP2, MP3, MP4, and QCISD, and corresponding spin-projection PMP2 and PMP3 with the same basis set (6-311+G * ). In the calculations, all electrons are correlated. The electronic transmission coefficient is calculated using the ab initio potential energy surface slopes and the coupling matrix element determined from the two-state model and the Slater-type d-electron wave functions. The pair distribution function is determined by using a new method presented here. The contact distance dependence and orientation dependence of relevant parameters and the applicability of the presented models are also discussed.