The spectrum of the cyclopropane molecule was measured in the region 2898.5 to 3157.3 cm-1 with Doppler-limited resolution using a difference frequency laser spectrometer. Deconvolution was used to further enhance the effective resolution in the main part of the highly perturbed spectrum. The region below ∼3060 cm-1 contains perpendicular bands, including the ν8 fundamental of species E′ in close anharmonic resonance with the E′ component of the state ν7 + ν9 + ν14 and with other E′ states, and the ν2 + ν9 band which borrows its intensity from ν8 via Fermi resonance. The ν2 + ν9 E′ state is also perturbed by anharmonic interactions with additional E′ states. A comprehensive analysis of this complex system of perpendicular bands based on a Hamiltonian model of the main interactions yielded much improved spectroscopic constants for the ν8 fundamental, for the ν2 + ν9 combination, and for the newly observed ν7 + ν9 + ν14 state, as well as information on seven tentatively identified perturbing states.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics
- Physical and Theoretical Chemistry