FAR-INFRARED LASER MAGNETIC-RESONANCE SPECTROSCOPY OF CH2CL (X2B1)

Far-infrared laser magnetic resonance (FIR-LMR) spectra of CH2 Cl-35 ( X2 B1) observed at three FIR wavelengths in the range 450 mum less-tha n-or-equal-to lambda less-than-or-equal-to 750 mum have been analyzed and assigned. The spectra were obtained using three different source r eactions, F + CH3Cl --> CH2Cl + HF, Cl + CH2CO --> CH2Cl + CO, and Na + CH2Cl2 --> CH2Cl + NaCl. The resonances at the three FIR wavelengths were attributed to a-dipole transitions involving relatively high rot ational states (12 less-than-or-equal-to N less-than-or-equal-to 20 an d 2 less-than-or-equal-to K less-than-or-equal-to 6). The spectra coul d be simulated satisfactorily based upon the molecular parameters deri ved by Endo et al. [Can. J. Phys. 62, 1347-1360 (1984)] from the milli meterwave spectrum of much lower rotational states of the radical. The agreement which was obtained shows that the CH2Cl radical possesses a rather rigid structure. (C) 1994 Academic Press, Inc.