THE OPTICAL-SPECTRUM OF HCSI

A new emission band system has been observed in the gas phase at aroun d 850 nm. This system correlates with absorption bands previously meas ured in a neon matrix and assigned to a triplet electronic transition of SiC. However, the gas phase bands display a clear doublet structure . Preliminary molecular parameters resulting from the rotational analy sis of the (000) - (000) band coincide with the expected values obtain ed by a recently published ab initio calculation carried out on the HC Si radical. We conclude that both the gas phase and the neon matrix sp ectra originate from the HCSi radical which is here identified for the first time.