We report a state-of-the-art synthesis and isolation procedure for 13 Lewis base iminium salts (LBI) of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), confirming their structures meticulously by different spectral data.
View Article and Find Full Text PDFMulti-dimensional quantum mechanical simulations are carried out to understand the multi-state and multi-mode vibronic interactions in the first six low-lying viz., X̃2B1, Ã2A1, B̃2B2, C̃2A2, D̃2A1, and Ẽ2B1 electronic states of c-C2H4O·+. Vibronic coupling theory is applied to study interactions among electronic states using symmetry selection rules.
View Article and Find Full Text PDFIn this article, the theoretical photoionization spectroscopy of the aziridine (C2H5N) molecule is investigated. To start with, we have optimized the geometry of this molecule at the neutral electronic ground state at the density functional theory/augmented correlation-consistent polarized valence triple zeta level of theory using the G09 program. The electronic structure calculations were restricted to the first six low-lying electronic states in order to account for the experimental photoelectron spectrum of the C2H5N molecule.
View Article and Find Full Text PDFVibronic coupling in the first eight electronic excited states of Pentafluorobenzene (PFBz) is investigated in this article. In particular, the vibronic coupling between the optically bright ππ* and optically dark πσ* states of PFBz is considered. A model 8 × 8 diabatic Hamiltonian is constructed in terms of normal coordinate of vibrational modes using the standard vibronic coupling theory and symmetry selection rule.
View Article and Find Full Text PDFMulti-state and multi-mode vibronic dynamics in the seven energetically low-lying (, , , , , , and ) electronic states of the acetaldehyde radical cation is theoretically studied in this article. Adiabatic energies of these electronic states are calculated by quantum chemistry methods. A vibronic coupling model of seven electronic states is constructed in a diabatic electronic basis to carry out the first-principles nuclear dynamics study.
View Article and Find Full Text PDFPhys Chem Chem Phys
July 2022
The Jahn-Teller (JT) and pseudo-Jahn-Teller (PJT) effects in the , and electronic states of the propyne radical cation are investigated with the aid of quantum chemistry calculations and first principles quantum dynamics simulations. For the latter, both time-independent and time-dependent quantum mechanical methods are employed. Standard vibronic coupling theory is used to construct a symmetry consistent vibronic Hamiltonian in a diabatic electronic basis.
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