Franck–Condon simulation of the photoelectron spectrum of [formula omitted] including Duschinsky effects

Abstract

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 2 - . Geometry optimizations and harmonic vibrational frequency calculations have been performed on the X ˜ 1 A 1 state of SO 2 and X ˜ 2 B 1 state of SO 2 - . Franck–Condon analyses and spectral simulation were carried out on the first photoelectron band of SO 2 - . The theoretical spectra obtained by employing CCSD(T)/6-311+G(2d,p) values are in excellent agreement with the experiment. In addition, the equilibrium geometric parameters, r e(OS) = 0.1508 ± 0.0005 nm and θ e(O–S–O) = 113.5 ± 0.5°, of the X ˜ 2 B 1 state of SO 2 - , are derived by employing an iterative Franck–Condon analysis procedure in the spectral simulation.