HYPERFINE-STRUCTURE OF THE SIC RADICAL

The millimeter-wave rotational spectrum of the free (SiC)-Si-29 radical in the X3PI ground state, produced in a low-pressure glow discharge through SiH4 and CO, was detected with the same reactive-molecule spectrometer used earlier to detect SiC and (SiC)-C-13. Eleven rotational transitions, all but two with resolved hyperfine structure, were measured between 195 GHz (J = 4 --> 5) and 372 GHz (J = 8 --> 9). Well-resolved hyperfine splittings in the three fine-structure ladders allow determination of the magnetic hyperfine constants to 2% or better.