Vibronic dynamics of electronic ground state of CH₂F₂⁺ and its deuterated isotopomer

Abstract

In continuation to our earlier work [Sarkar et al., Mol. Phys. 2015, 113, 3073–3084], we present here the vibronic structure and nonradiative decay dynamics of energetically low-lying electronic states of CH₂F₂⁺. Interesting comparison is made with the results obtained for the deuterated isotopomer CD₂F₂⁺. The results are compared with both broad band as well as high-resolution experimental spectroscopy data available in the literature. The progression of vibrational modes in the spectra is identified, assigned and discussed in relation to the assignments available in the literature. Both time-independent and time-dependent quantum mechanical methods are used to carry out nuclear dynamics calculations. The underlying potential energy surfaces and their coupling surfaces are constructed by rigorous ab initio quantum chemistry calculations.