FOURIER-TRANSFORM EMISSION-SPECTROSCOPY OF TRIPLET C-13(3)

We describe the construction of a liquid-nitrogen-cooled multireflecti on emission cell. A combination of very small gas input apertures and very rapid evacuation through a combination of mechanical and booster pumps provides for a rapid replenishment of discharge-formed material in the cell. This cell is an excellent source for the study of the C-3 radical in the triplet manifold of electronic states. Emission bands of triplet C-3 were observed in the region around 6500 cm(-1) with a F ourier transform spectrometer. The strongest feature corresponds to th e (000)-(000) band of the b(3) Pi(g) --> ($) over cap a(3) Pi(n) elect ronic transition, which for C-12(3) was observed and analyzed by Sasad a et al. (J. Chem. Phys. 94, 2401-2407, 1991). We have observed this b and for C-13(3), and report the line positions and analysis in this pa per. (C) 1995 Academic Press, Inc.