Study on the structure and property for the NO2+NO2- electron transfer system

The structures and the properties of the NO2 + NO2- electron transfer syste m are studied with ab initio calculations at the B3LYP/6-311 + G* basis set level for the three selected structures: three species favor the structure of 'head to head'. The nitrogen dioxide molecule separation distances comp uted using the DFT/B3LYP method were found to agree with the second order o f Moller-Plesset perturbation theory lever (MP2) results. The 351.1 run (3. 532 eV) photoelectron spectrum of the nitrite anion (NOD is obtained. The e lectron affinity of NO2 is found to be 2.273 +/- 0.005 eV, which leads to t he heat of formation Delta H-f(0)0(NO2-) = -183.4 +/- 0.9 kJ/mol. It shows there are relatively strong interactions between them. Additionally, the ge ometry of transition state is also obtained by the linear coordinate method . From the analysis of the charge on the transition state and the isolated state, the reaction kinetics mechanism was derived. The activation energy a nd the coupling matrix element of the rate constant of the ET reaction are also calculated. According to the reorganization energy of the ET reaction, the values obtained from the George-Griffith-Marcus (GGM) method (the cont ribution only from diagonal elements of force constant matrix) are larger t han those obtained from the Hessian matrix method (including the contributi on from both diagonal and off-diagonal elements), which suggests that the c oupling interactions between different vibrational modes are important to t he inner-sphere reorganization energy for the ET reactions in gaseous phase . (C) 2001 Elsevier Science B.V. All rights reserved.