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Title: Observation of b 2 symmetry vibrational levels of the SO 2C 1B 2 state: Vibrational level staggering, Coriolis interactions, and rotation-vibration constants

Here, the C 1B 2 state of SO 2 has a double-minimum potential in the antisymmetric stretch coordinate, such that the minimum energy geometry has nonequivalent SO bond lengths. However, low-lying levels with odd quanta of antisymmetric stretch (b 2 vibrational symmetry) have not previously been observed because transitions into these levels from the zero-point level of the X ~ state are vibronically forbidden. We use IR-UV double resonance to observe the b 2 vibrational levels of the C state below 1600 cm –1 of vibrational excitation. This enables a direct characterization of the vibrational level staggering that results from the double-minimum potential. In addition, it allows us to deperturb the strong c-axis Coriolis interactions between levels of a 1 and b 2 vibrational symmetry, and to determine accurately the vibrational dependence of the rotational constants in the distorted C electronic state.
ORCiD logo [1] ;  [1] ;  [1] ; ORCiD logo [1]
  1. Massachusetts Institute of Technology, Cambridge, MA (United States). Dept. of Chemistry
Publication Date:
Grant/Contract Number:
FG02-87ER13671; FG0287ER13671
Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 144; Journal Issue: 14; Journal ID: ISSN 0021-9606
American Institute of Physics (AIP)
Research Org:
Massachusetts Institute of Technology, Cambridge, MA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Contributing Orgs:
Massachusetts Institute of Technology
Country of Publication:
United States
74 ATOMIC AND MOLECULAR PHYSICS; SO2; sulfur dioxide; pseudo Jahn-Teller; vibronic coupling; Coriolis effects; rotation constants; wave functions; level splitting; ultraviolet light
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1247601