Vibrational Spectroscopy of Trichloroethene Cation by Vacuum Ultraviolet Pulsed Field Ionization-photoelectron Method

The vacuum ultraviolet（VUV）pulsed field ionization-photoelectron（ PFI-PE）spectrum for trichloroethene（ClCH=CCl2）has been measured in the energy range of 76400-79650 cm-1 . The vibrational bands resolved in the VUV-PFI-PE spectrum are assigned based on ab initio vibrational frequencies and calculated Franck-Condon factors for the ionization transitions，yielding eleven vibrational frequencies for ClCH=CCl2+：v1+=148 cm-1，v2+= 80 cm-1，v3+=286 cm-1，v4+=402 cm-1，v5+= 472 cm-1，v6+=660 cm-1，v7+=875 cm-1，v8+=990 cm-1，v9+=1038 cm-1，v10+=1267 cm-1，and v11+=1408 cm-1. These measurements along with the frequency v12+=3073 cm-1 determined in the recent VUV-infrared photo-induced ionization study have provided the complete set of twelve experimental vibrational frequencies for ClCH = CCl2+ in its ground electronic state. On the basis of the spectral simulation of the origin VUV-PFI-PE vibrational band，we have determined the IE（ClCH=CCl2）to be（76441.7±2.0）cm-1（（9.4776±0.0002）eV）.