CASSCF study of energies and lifetimes of temporary negative ions of CH2Br2, CHClBr2 and CCl3Br

The temporary negative ions of CH2Br2, CHClBr2 and CCl2Br are investigated using the stabilization method (based on scaling the exponents of diffuse basis functions) and CASSCF calculations. The CASSCF energies are analytically continued into the complex plane to obtain the energies and lifetimes of the resonance states. It is suggested that the procedure adopted in this work provides a computationally simple approach to the study of quasibound temporary negative ions. The results obtained are compared with available experimental data.