r Sharafdini - Department of Chemistry, Payamenoor University of Sirjan, Sirjan, Iran,

The vibrationally resolved bands corresponding to the ionization SeBr2(X1A1) → SeBr2 +(X2B1) has been simulated using Franck-Condon analyses in the harmonicoscillator approximation. The photoelectron spectra of SeBr2 has been simulated with the computed Franck-Condon factors inthe harmonic oscillator approximation. The Duschinsky rotations among the normal modes of two ground electronic states of speciesinvolved in the transition are fully taken into account. The obtained ionization energiy of SeBr2 is in reasonable agreement with the experimentally determined values. The spectral simulations of vibrational structures including frequency changes and Duschinsky rotation upon the electronicexcitation are in agreement with the experimental results

photoelectron spectroscopy, Franck-Condon analysis, Duschinsky rotation