INFRARED-LASER SPECTROSCOPY OF THE NU(2) BAND OF DIFLUOROCARBENE (CF2)

The spectrum of the nu(2) fundamental band of CF2 ((X) over tilde(1)A( 1)) has been recorded at Doppler-limited resolution between 638 and 70 6 cm(-1) using a diode laser spectrometer. This band is predicted to b e about 250 times weaker than the symmetric stretching vibration of CF 2, and a multiple pass cell with an effective absorption length of 25 m was therefore employed in the measurement. A total of 217 transition s with J less than or equal to 40 and K-a less than or equal to 7 were assigned and used in a least-squares fit in which the ground state co nstants were fixed at their microwave values and the nu(2) = 1 paramet ers were floated. The band origin was determined to be 666.24922(9) cm (-1). (C) 1995 Academic Press, Inc.