VIBRATIONAL AND VIBRATION-ROTATIONAL SPECTROSCOPY OF CBRCLF2 (HALON-1211)

The infrared spectrum of Halon-1211, CBrClF2, in a supersonic jet expa nsion has been measured by high resolution FTIR spectroscopy and the r otational structure of the v(1) B-type band at 1100 cm(-1) and the v(7 ) C-type band at 1151 cm(-1) have been analyzed. Upper state rotationa l constants have been obtained for the (CBrClF2)-Br-79-Cl-35 and (CBrC lF2)-Br-81-Cl-35 isotopomers, and these have been used to simulate the band structure, enabling the rotational temperature in the jet to be estimated at 40 K. In addition, low resolution far infrared and mid in frared spectra along with gas phase Raman spectra of CBrClF2 have been recorded at room temperature and the vibrational fundamentals more co mpletely assigned. These results are compared with the values predicte d by molecular orbital calculations at the LANLlDZ, 6-311G* and MP2/6 -311G* levels of theory.