THE INFRARED-LASER SPECTRUM OF CF2=CHF NEAR 1360 CM(-1) - ROVIBRATIONAL ANALYSIS OF THE NU-(3) FUNDAMENTAL

The infrared spectrum of CF2=CHF has been studied in the vg fundamenta l region around 1360 cm(-1) at a resolution of about 0.002 cm(-1) usin g a tunable diode laser spectrometer. This vibration of symmetry speci es A' gives rise to an alb hybrid band with a prevalent contribution o f the b-type component. Both J and K structures have been resolved in different subbranches and the rovibrational analysis led to the assign ment of more than 2000 lines with J less than or equal to 71, K-a less than or equal to 26, and K-c less than or equal to 71. The v(3) band is affected by first-order b-type Coriolis resonance with the v(10) 2Y(12) and v(7) + v(10) states, and the strongest interaction effect h as been found for the K-a' = 11 and 12 levels; some crossings for low K,values, due to the perturbation with the v(10) + 2v(12) vibration, h ave also been located. Using Watson's A-reduction Hamiltonian in the I ' representation, about 1700 transitions, free of major resonance cont ribution, provided a set of effective molecular parameters for the v(3 ) = 1 state. Although none of the interacting levels have been observe d, a few parameters for the v(10) + 2v(12) combination have been deter mined from the perturbation effects near the crossings. (C) 1995 Acade mic Press, Inc.