Theoretical Study on Reactivity of Electron Transfer in Model—System of Oxidation of α—Amino Carbon—centered Radical by O2

Electron transfer reaction between a simplified model model molecule of α－amino carbon-centered radical and O2 has studied with ab initio calculations at the MP2/6-31 G^**//UHF/6-31 G^** level,The reactant complex and the ion pair complex have been optimized and employed to perform calculation of the reaction heat and the reorganization energy,Solvent effects have been considered by applyning the conductor-like screening model,Theoretical results show that the highly endothermic charge separation process ,in which one electron transfers from the α－amino carbon-centered radical to O2,so as to form an ion pair complex,is difficult to occur in gas-phase,By apply-ing an external electronic field to prepare the charge-locallized molecular orbitals,the charge-separated state has been obtained using the initial-guess-induced self-consistent field technique,The theoretical investigations indicate that the solvent effect in the process of the oxidation of α-animo carbon-centered radical by O2 is remarkable.From the rate constant estima-tion ,it can be predicted that the oxidation of the model donor molecule by O2 can proceed,but not very fast.A peroxyl radi-cal compound has been found to be a competitive intermediate in the oxidation process.

Theoretical Study on Reactivity of Electron Transfer in Model‐System of Oxidation of α ‐Amino Carbon‐centered Radical by O2

Electron transfer reaction between a simplified model molecule of α‐amino carbon‐centered radical and O₂ has been studied with ab initio calculations at the MP2/6‐31 ++ G**//UHF/6‐31 ++ G** level. The reactant complex and the ion pair complex have been optimized and employed to perform calculations of the reaction heat and the reorganization energy. Solvent effects have been considered by applying the conductor‐like screening model. Theoretical results show that the highly endothermic charge separation process, in which one electron transfers from the α‐amino carbon‐centered radical to O₂, so as to form an ion pair complex, is difficult to occur in gas‐phase. By applying an external electronic field to prepare the charge‐localized molecular orbitals, the charge‐separated state has been obtained using the initial‐guess‐induced self‐consistent field technique. The theoretical investigations indicate that the solvent effect in the process of the oxidation of α‐amino carbon‐centered radical by O₂ is remarkable. From the rate constant estimation, it can be predicted that the oxidation of the model donor molecule by O₂ can proceed, but not very fast. A peroxyl radical compound has been found to be a competitive intermediate in the oxidation process.