Microwave spectroscopy of the allenyloxy radical (CH{sub 2}=CCHO)

Journal Article · Tue Jan 21 04:00:00 EST 2014 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4862057· OSTI ID:22255247

Umeki, Hiroya; Nakajima, Masakazu; Endo, Yasuki ^[1]

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1. Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

Pure rotational spectra of the allenyloxy radical (CH{sub 2}=CCHO) were observed by Fourier transform microwave (FTMW) and FTMW-millimeter wave double-resonance spectroscopy. Molecular constants including the hyperfine interaction constants of CH{sub 2}=CCHO in the {sup 2}A{sup ″} ground electronic state were precisely determined. Ab initio calculations indicate that CH{sub 2}=CCHO has a linear C−C−C backbone with C{sub s} symmetry, where the formyl group is in the C{sub s} plane and perpendicular to the methylene group. The determined rotational constants and the inertial defect agree well with those derived from the calculations, implying that the calculated molecular structure is reasonable. The fine and hyperfine constants also agree with those derived from the calculated spin density, where the unpaired electron is located mainly on the central carbon atom. The ground state CH{sub 2}=CCHO can, thus, be described as taking the formylvinyl (CH{sub 2}=Ċ−CH=O) form rather than as the allenyloxy (CH{sub 2}=C=CH−O{sup .}) form.

• OSTI ID: 22255247
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 3 Vol. 140; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
DENSITY
ELECTRONS
FOURIER TRANSFORMATION
GROUND STATES
INTERACTIONS
MICROWAVE RADIATION
MOLECULAR STRUCTURE
RADICALS
SPECTRA
SPECTROSCOPY