Title

The far-infrared and microwave spectra of the CH radical in the v = 1 level of the X2Π state

Authors

Michael Jackson, Central Washington University
Lyndon R. Zink, University of Wisconsin-La Crosse
Michael C. McCarthy, Harvard University
Luis Perez, University of Oxford
John M. Brown, University of Oxford

Document Type

Article

Department or Administrative Unit

Physics

Publication Date

2-2008

Abstract

Transitions between the spin–rotational levels of the ¹²CH radical in the v = 1 level of the X²Π state have been studied by the technique of laser magnetic resonance at far-infrared wavelengths. The data have been combined with a measurement of lambda-doubling transition frequencies at 7 GHz to determine an improved set of molecular parameters for CH in the v = 1 level. The parameters provide information on the effects of vibrational excitation on the structural properties of CH. Accurate predictions of the transition frequencies between the low-lying levels of the radical in the absence of a magnetic field have also been made.

Small inconsistencies in the least-squares fit of the laser magnetic resonance data prompted re-measurement of three far-infrared laser frequencies, the 122.5 μm line of CH₂F₂ pumped by 9R(22), the 122.5 μm line of CH₂F₂ pumped by 9P(8) and the 554.4 μm line of CH₂CF₂ pumped by 10P(14). The new measurements differ by as much as 3.8 MHz from those made previously and are more accurate; they also remove the inconsistencies in the fit. The re-measured frequencies of the two 122.5 μm lines are identical within experimental error which suggests that the far-infrared lasing transition is the same, namely the ^rR₂₃(32) transition in the v₉=1 level of CH₂F₂.

Comments

This article was originally published in Journal of Molecular Spectroscopy. The full-text article from the publisher can be found here.

Due to copyright restrictions, this article is not available for free download from ScholarWorks @ CWU.

Recommended Citation

Jackson, M., Zink, L. R., McCarthy, M. C., Perez, L., & Brown, J. M. (2008). The far-infrared and microwave spectra of the CH radical in the v=1 level of the X2Π state. Journal of Molecular Spectroscopy, 247(2), 128–139. https://doi.org/10.1016/j.jms.2007.11.001

Journal

Journal of Molecular Spectroscopy

Rights

Copyright © 2007 Elsevier Inc. All rights reserved.