FOURIER-TRANSFORM INFRARED-EMISSION SPECTROSCOPY OF SH

The infrared emission spectrum of SH has been observed in the 1850-280 0 cm(-1) spectral region using a Fourier transform spectrometer. The m olecules were excited in a microwave discharge source and the spectra have been recorded at a resolution of 0.005 cm-(1). The observed spect ra consist of 1-0, 2-1, and 3-2 vibration-rotation bands of the X(2) P i(1/2), spin component and 1-0, 2-1, 3-2, and 4-3 bands of the X(2) Pi (3/2) spin component. The present data were combined with the previous vibration-rotation, pure rotation, and Lambda-doubling measurements i n the ground state to yield an improved set of molecular constants. Th e principal equilibrium constants obtained from this work are: omega(c ) = 2696.2475(58) cm(-1), omega(e),x(e) = 48.7420(28) cm(-1), B-e = 9. 600247(51) cm(-1), alpha(c) = 0.27990(10) cm(-1), and r(e) = 1.340614( 4) Angstrom. (C) 1995 Academic Press, Inc.