Abstract
A b initio molecular quantum mechanics has been used to study the four lowest electronic states of the nitrate free radical at the D3h geometry deduced from experiment (1985) by Ishiwata, Tanaka, Kawaguchi, and Hirota. Basis sets ranging from double zeta (9s5p/4s2p) to triple zeta plus double polarization quality were used. Both self-consistent-field (SCF) and configuration interaction (CI) wave functions were employed, with molecular orbitals determined for the various electronic states of NO3 and for the ground state NO−3 anion. The CI wave functions included single (S), double (D), and (in some cases) triple (T) excitations. The CISDT wave functions included as many as 511 474 configurations in C2v point group symmetry. The predicted energetic position of the 2E′ state agrees well with the known T0=15 100 cm−1. The 2E″ state, found to be the lowest excited electronic state of NO3, is predicted to lie at a vertical excitation energy of ∼3600 cm−1. The relationship between this prediction and the 1986 experiments by Kawaguchi, Ishiwata, Tanaka, and Hirota suggesting an excited electronic state at 1490 cm−1 is discussed.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
