Franck-Condon simulation of the photoelectron spectrum of SO2- including Duschinsky effects

A theoretical method to calculate multidimensional Franck-Condon factors including Duschinsky effects is described and used to simulate the photoelectron spectrum of the anion SO. Geometry optimizations and harmonic vibrational frequency calculations have been performed on the XA(1) state of SO2 and (XB1)-B-2 state of SO2. Franck-Condon analyses and spectral simulation were carried out on the first photoelectron band of SO2. The theoretical spectra obtained by employing CCSD(T)/6-31 I+G(2d,p) values are in excellent agreement with the experiment. In addition, the equilibrium geometric parameters, r(c)(OS) = 0.1508 +/- 0.0005 nm and theta(e)(O-S-0) = 113.5 +/- 0.5 degrees, of the (XB1)-B-2 state of SO2, are derived by employing an iterative Franck-Condon analysis procedure in the spectral simulation. (c) 2005 Elsevier B.V. All rights reserved.