High resolution infrared spectroscopy of [1.1.1]propellane: The region of the ν₉ band

Journal Article · Mon Nov 01 04:00:00 EDT 2010 · Journal of Molecular Spectroscopy

DOI:https://doi.org/10.1016/j.jms.2010.08.008· OSTI ID:1001115

Maki, Arthur; Weber, Alfons; Nibler, Joseph W.; Masiello, Tony; Blake, Thomas A.; Kirkpatrick, Robynne

The region of the infrared-active band of the ν₉ CH2 bending mode [1.1.1]propellane has been recorded at a resolution (0.0025 cm^-1) sufficient to distinguish individual rovibrational lines. This region includes the partially overlapping bands ν₉ (e') = 1459 cm^-1, 2ν₁₈ (l = 2, E') = 1430 cm^-1, ν₆ + ν₁₂ (E') = 1489 cm-1, and ν₄ + ν₁₅ (A₂") = 1518 cm^-1. In addition, the difference band ν₄ - ν₁₅ (A2") was observed in the far infrared near 295 cm^-1 and analyzed to give good constants for the upper ν₄ levels. The close proximities of the four bands in the ν₉ region suggest that Coriolis and Fermi resonance couplings could be significant and theoretical band parameters obtained from Gaussian ab initio calculations were helpful in guiding the band analyses. The analyses of all four bands were accomplished, based on our earlier report of ground state constants determined from combination differences involving more than 4000 pairs of transitions from five fundamental and four combination bands. This paper presents the analyses and the determination of the upper state constants of all four bands in the region of the ν₉ band. Complications were most evident in the 2ν₁₈ (l = 2, E') band, which showed significant perturbations due to mixing with the nearby 2ν₁₈ (l = 0, A₁') and ν₄ + ν₁₂ (E') levels which are either infrared inactive as transitions from the ground state, or, in the latter case, too weak to observe. Finally, these complications are discussed and a comparison of all molecular constants with those available from the ab initio calculations at the anharmonic level is presented.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1001115
• Report Number(s): PNNL-SA-73401; 20907; KP1704020
• Journal Information: Journal of Molecular Spectroscopy, Journal Name: Journal of Molecular Spectroscopy Journal Issue: 1 Vol. 264; ISSN 0022-2852
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Ab initio DFT study
Anharmonic frequencies
CORIOLIS FORCE
ENERGY-LEVEL TRANSITIONS
Environmental Molecular Sciences Laboratory
FERMI RESONANCE
GROUND STATES
HYDROCARBONS
High resolution infrared spectrum
INFRARED SPECTRA
Propellane
RESOLUTION
Rovibrational constants
SPECTROSCOPY