Ground state dynamics of NO3: Multimode vibronic borrowing including thermal effects

摘要

TheXthinsp;2A2rsquo;band of the photoelectron spectrum of NOminus;3is theoretically calculated in the framework of a multimode vibronic coupling model. Linear coupling between and within theXthinsp;2A2rsquo;and theBthinsp;2Ersquo;electronic states of NO3is found to be the important mechanism governing the dynamics. The necessary coupling constants are obtained from the ionization potentials of NOminus;3calculated at different geometries usingabinitioGreenrsquo;s functions. Comparison of the theoretical with experimental results lsqb;A. Weaver, D. W. Arnold, S. E. Bradforth, and D. M. Neumark, J. Chem. Phys.94(3), 1740 (1991)rsqb; for the PE spectrum shows good agreement if a temperature of the NOminus;3anion of 455 K in the experiment is assumed. A general theoretical treatment of thermal effects in vibronically coupled electronic states is presented. The ground electronic state potential surface of NO3is discussed in the framework of the vibronic coupling model. A shallow minimum at aC2vgeometry with a barrier height of 0.006 eV relative to the minimum energyD3hconfiguration is found. It is too weak to deform the effective geometry of the molecule fromD3htoC2v. Modehyphen;mode coupling is found to play a relevant role in the ground electronic state of NO3, in general.