1. Electronic structure of the para-benzoquinone radical anion revisited
- Author
-
Ksenia B. Bravaya and Alexander A. Kunitsa
- Subjects
010304 chemical physics ,Absorption spectroscopy ,Chemistry ,General Physics and Astronomy ,Context (language use) ,Electronic structure ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Ion ,Excited state ,0103 physical sciences ,Physical and Theoretical Chemistry ,Perturbation theory ,Atomic physics ,Ground state ,Excitation - Abstract
Photoinduced dynamics of the para-benzoquinone anion features a subtle interplay between autodetachment and non-adiabatic transitions involving a dense manifold of resonances. We report the results of a multistate multireference perturbation theory study of the electronic structure of the para-benzoquinone anion in the ground, several low-lying excited electronic states, and in the lowest electron-detached state (the ground state of the neutral molecule). The electronic structure calculations revealed non-planar equilibrium geometry of the (2)Au excited state of the anion, but the effects of non-planarity on the shape of the absorption spectrum are found to be minor. Despite the large differences in the vertical excitation energies for the two lowest bright excited states, (2)Au (2.55 eV) and (2)B3u (2.93 eV), the simulated absorption spectra significantly overlap for the photon energies below 2.7 eV. Relevant minimum energy crossing points have been located using the CASSCF method. Excited-state deactivation channels are discussed in the context of accurate energetics and recent spectroscopic studies of the para-benzoquinone anion.
- Published
- 2016