Synchrotron radiation VUV double photoionization of CHF2Cl

VUV double photoionization of CHF2Cl in an energy region 32-40 eV was investigated with photoionization mass spectroscopy by using synchrotron radiation. The double ionization energy of CHF2Cl and appearance energies for its main fragment dications (CHCl2+, CF22+ and CHFCl2+), were determined with photoionization efficiency spectroscopy for the first time. The single point energies of CHF2Cl and its parent dication (CHF2Cl2+) were calculated using Gaussian 03 program and density functional theory (DFT and B3LYP functional). The vertical double ionization energy of CHF2Cl was predicted by using B3LYP method and empirical equation. According to our research results, the experimental double ionization energy of CHF2Cl is in good agreement with the theoretically calculated vertical double ionization energy. The mechanism of double photoionization of CHF2Cl was discussed based on the comparison of our experimental results with those predicted theoretically.