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Rydberg spectra of trans-1,2-dibromoethylene
1Department of Chemistry, University of Western Ontario, London, Ontario N6A 5B7, Canada.
Abstract:
(2+1) resonance-enhanced multiphoton ionization spectra of jet-cooled trans-1,2-dibromoethylene are reported for the first time. The two-photon spectral region between 149.7 and 141.2 nm was examined. A 4p(z)<--pi Rydberg transition between 66,800 and 68,000 cm(-1) with A(g) excited state symmetry was analyzed, as well as two 4f<--pi Rydberg transitions with B(g) excited state symmetry and one 4f<--pi Rydberg transition with A(g) excited state symmetry between 68,000 and 70,800 cm(-1). All Rydberg transitions observed in this work belong to series that converge to the first ionization potential of the molecule. The short vibrational progressions observed involve two totally symmetric in-plane normal modes: C=C-H bending (nu(3)) and C=C-Br bending (nu(5)) with average excited state frequencies of 829 and 226 cm(-1), respectively.
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