Insights into the Photoelectron Spectroscopy of Chlorofluoroethenes Studied by Density-Functional and Coupled-Cluster Theories.

The first two ionic states of chlorofluoroethenes were studied by using both time-independent and time-dependent density-functional theories. We calculated the equilibrium geometries and harmonic vibrational frequencies of 1,1-, cis-, and trans-C2H2FCl and their cations by using the B3LYP and B3PW91 functionals together with the cc-pVTZ and aug-cc-pVTZ basis sets. Franck-Condon factors were computed by the method developed in our group, in which the Duschinsky effect was treated explicitly.