Ab initio constructed diabatic surfaces of NO2 and the photodetachment spectra of its anion

• Published in: The Journal of chemical physics Vol. 143; no. 24; p. 244307
• Main Authors: Mukherjee, Saikat, Mukherjee, Bijit, Sardar, Subhankar, Adhikari, Satrajit
• Format: Journal Article
• Language: English
• Published: United States American Institute of Physics 28.12.2015
• Subjects: Adiabatic flow; Anions; Coupling; Electron states; Electronic structure; Hilbert space; Intersections; Jahn-Teller effect; Nitrogen dioxide; Photodetachment; Potential energy
• ISSN: 0021-9606; 1089-7690; 1089-7690
• DOI: 10.1063/1.4938526

A thorough investigation has been performed for electronic structure, topological effect, and nuclear dynamics of NO2 molecule, where the adiabatic potential energy surfaces (PESs), conical intersections between the ground (X2A1) and the first excited state (A2B2), and the corresponding non-adiabatic coupling terms between those states are recalculated [Chem. Phys. 416, 11 (2013)] to achieve enough accuracy in dynamics. We employ beyond Born-Oppenheimer theory for these two state sub-Hilbert space to carry out adiabatic to diabatic transformation (ADT) to obtain the ADT angles and thereby, to construct single-valued, smooth, and continuous diabatic PESs. The analytic expressions for the adiabatic PESs and ADT angles are provided to represent a two-state three-mode diabatic Hamiltonian of NO2 for performing nuclear dynamics to calculate the photo-electron spectra of its anion. It appears that not only Jahn-Teller type coupling but also Renner-Teller interaction contributes significantly on the overall spectrum. The coupling between the electronic states (X2A1 and A2B2) of NO2 is essentially through the asymmetric stretching mode, where the functional form of such interaction is distinctly symmetric and non-linear.