High-resolution rovibrational analysis of the Nu4 band of cis-1,2-difluoroethylene.
The diode laser spectrum of cis-1,2-CHF=CHF has been measured and analyzed in the nu4 fundamental region near 1016 cm(-1). This vibration of symmetry species A1 corresponds to the C-F symmetric stretching motion and gives rise to a strong b-type band. The rovibrational analysis, extended to the P, Q, and R branches, led to the identification of 2800 lines with J < or = 62, Ka < or = 18, Kc < or = 62. The assigned transitions free of major resonance contributions, fitted using Watson's A-reduction Hamiltonian in the Ir representation, yielded a set of spectroscopic parameters up to the quartic coefficients for the V4 = 1 state. Several perturbation effects occur throughout the band, mainly caused by the first-order c-type Coriolis interaction with the nu5 + nu11, vibrational state. Even though no transitions to the perturbing level were observed, the band orign and the rotational constants for the perturber were determined from a dyad model which includes the Coriolis interaction term.
Visinoni
R
R
Università di Venezia, Dipartimento di Chimica Fisica, Italy. visinon@unive.it
Giorgianni
S
S
Stoppa
P
P
Ghersetti
S
S
D005030:Ethylenes / Q000737:chemistry*; D013055:Spectrophotometry, Infrared / Q000379:methods*; D013223:Statistics as Topic
D005030:Ethylenes; C418472:1,2-fluoroethene