dc.creator Stancu, G. D. en_US dc.creator Ropcke, J. en_US dc.creator Davies, P. B. en_US dc.date.accessioned 2006-06-15T20:59:03Z dc.date.available 2006-06-15T20:59:03Z dc.date.issued 2004 en_US dc.identifier 2004-WJ-02 en_US dc.identifier.uri http://hdl.handle.net/1811/21531 dc.description $^{a}$C. Yamada and E. Hirota, J.Chem. Phys. 78, (2) 669 (1983). en_US dc.description Author Institution: INP-Greifswald; Department of Chemistry, University of Cambridge en_US dc.description.abstract The determination of methyl radical concentrations in terrestrial and astronomical sources using infrared spectroscopy relies on the availability of accurate line strengths and transition dipole moments. The $\nu_{2}$ fundamental of $CH_{3}$ near $606 cm^{-1}$ is particularly useful for this purpose but the current value of its transition dipole moment is uncertain by at least $20%$. We have measured the line strength of 9 Q-branch lines of the $2^{1}_{0}$ band of $CH_{3}$ from Q(1,1) to Q(12,12) using diode laser absorption spectroscopy. The method is based on following the recombination rate of methyl radicals in a pulsed discharge in tertiary butyl peroxide heavily diluted in $argon^{a}$. The translational, rotational and vibrational temperatures of the radical were precisely determined from line widths and relative line intensities in both the $\nu_{2}$ fundamental and hot bands. The new value of the transition dipole moment is $0.22 \pm 0.02$ D which is compatible with most previous measurements and calculations, and with the transition dipole moment of the $\nu_{3}$ band. en_US dc.format.extent 313314 bytes dc.format.mimetype image/jpeg dc.language.iso English en_US dc.publisher Ohio State University en_US dc.title TRANSITION DIPOLE MOMENT AND LINE STRENGTHS FOR THE $\nu_{2}$ FUNDAMENTAL BAND OF THE METHYL RADICAL en_US dc.type article en_US
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