LABORATORY SPECTROSCOPY OF MGNC - THE 1ST RADIOASTRONOMICAL IDENTIFICATION OF MG-BEARING MOLECULE

The linear MgNC radical was detected, for the first time, by laboratory microwave spectroscopy, and six unidentified lines in IRC +10216 reported by Guelin et al. (1986) were assigned to the transitions of this radical. The radical was produced in a free space absorption cell by a DC discharge in a mixture of magnesium vapor, argon, and cyanogen. Observed spectral lines in the 250-370 GHz region were analyzed by using the 2SIGMA energy level expression, to give the rotational, centrifugal distortion and spin-rotation constants: B0 = 5966.8969(24) MHz, D0 = 0.004 2338(35) MHz, H-0 = 0.308(16) x 10(-7) MHz, and gamma0 = 15.219(13) MHz, with one standard deviation in parentheses.