Intramolecular vibrational relaxation and forbidden transitions in the SEP spectrum of acetylene

Journal Article · Sat Aug 15 00:00:00 EDT 1992 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.463021· OSTI ID:7034932

Jonas, D M; Solina, S A.B.; Rajaram, B; Silbey, R J; Field, R W ^[1]; Yamanouchi, K; Tsuchiya, S ^[2]

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1. Department of Chemistry and George R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)
2. Department of Pure and Applied Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153 (Japan)

{ital {tilde A}} {sup 1}{ital A}{sub {ital u}}{r arrow}{ital {tilde X}} {sup 1{Sigma}}{sub {ital g}}{sup +} SEP spectra of acetylene near {ital E}{sub VIB}=7000 cm{sup {minus}1} show that Darling--Dennison resonance between the {ital cis}- and {ital trans}-bending vibrations is the {ital first} {ital step} in a series of anharmonic resonances which can transfer nearly all the vibrational energy out of the Franck--Condon bright states at higher energy. In addition to allowed {vert bar}{Delta}{ital K}{vert bar}{equivalent to}{vert bar}{ital K}{prime}{minus}l{double prime}{vert bar}=1 rotational transitions, nominally forbidden {vert bar}{Delta}{ital K}{vert bar}=0,2,3 rotational transitions have also been observed due to axis-switching and rotational-l-resonance. Although the range of detectable fluorescence dips is only about 30, the range of detectable SEP intensities in these spectra is probably about 500.

• DOE Contract Number: FG02-87ER13671
• OSTI ID: 7034932
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 97:4; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

664200* -- Spectra of Atoms & Molecules & their Interactions with Photons-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
ACETYLENE
ALKYNES
ENERGY LEVELS
ENERGY-LEVEL TRANSITIONS
EXCITED STATES
FLUORESCENCE
FORBIDDEN TRANSITIONS
HYDROCARBONS
INFRARED SPECTRA
LUMINESCENCE
ORGANIC COMPOUNDS
RESONANCE
ROTATIONAL STATES
SPECTRA
VIBRATIONAL STATES