15min:
INFRARED EMISSION STUDIES OF THE A3Sigma--X3Pi ELECTRONIC TRANSITION OF SiC.

M. N. DEO AND K. KAWAGUCHI, Nobeyama Radio Observatory, Minamimaki, Minamisaku, Nagano, 384-1305, Japan.

The gas phase infrared emission spectrum of the A3Sigma- - X3Pi electronic transition of SiC has been observed using Fourier transform spectrometer. The SiC radical was generated by a dc discharge in a flowing mixture of (CH3)6Si2 and He. Three bands 1-0 (4577.8 cm-1), 0-0 (3723.1 cm-1) and 0-1 (2769.8 cm-1) have been observed, out of these the last two were observed for the first time. Altogether more than 1100 transitions have been assigned and these data were simultaneously least squares fitted and obtained the molecular constants for SiC in the A3Sigma- and X3Pi electronic states. The vibrational frequency nu0 in the A state was determined to be 854.6994(7) cm-1, which is close to the matrix result 854.2 cm-1.