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High-Resolution FTIR Spectroscopy Using a Jet: Sampling the Rovibrational Spectrum of 12CH4
1Faculte des Sciences, Universite Libre de Bruxelles, Roosevelt Ave., 50, Brussels, B-1050, Belgium
Abstract:
We have recorded high-resolution absorption spectra of 12CH4 cooled in a jet, using a Fourier transform interferometer. The expected nuclear spin symmetry conservation in the jet is exhibited from data recorded around 3000 cm-1 showing the relative intensity of the lines starting from the J" = 2 para and ortho levels. Spectra recorded around 4300 cm-1 are used to validate existing rovibrational parameters. Spectra recorded around 6000 cm-1 allow new rovibrational assignments to be performed in the N = 4 polyad. In particular, lines in the nu1 + nu3 band are identified for the first time. Copyright 1998 Academic Press. Copyright 1998Academic Press
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