THE MICROWAVE SPECTRUM AND MOLECULAR STRUCTURE OF 2-CHLORO-1,1-DIFLUOROETHYLENE AND PROGRESS TOWARDS ITS COMPLEXES WITH ARGON AND HYDROGEN FLUORIDE

Author Institution: Department of Chemistry, Amherst College, P.O. Box 5000, Amherst, MA 01002-5000Substitution of fluorine for hydrogen in 1,1-difluoroethylene leads to the observation of unexpected, but ultimately understandable, structures for the complexes of 1,1,2-trifluoroethylene with both hydrogen fluoride} \textbf{\underline{126},} \textit{in press} (2006).} and acetylene.}$ Ohio State University International Symposium on Molecular Spectroscopy}, RE12 (2006).} As a first step towards investigating the effect of chlorine substitution on the same carbon atom, it is necessary to refine the molecular structure of 2-chloro-1,1-difluoroethylene available in the literature.} \textbf{\underline{55},} 1473 (1959); S. Chandra, \textit{J. Phys. Chem.} \textbf{\underline{71},} 1927 (1967).} Fourier transform microwave spectra of six isotopomers of 2-chloro-1,1-difluoroethylene are obtained in the 7--21 GHz region. Strong $b$-type and weaker $a$-type transitions, which are split by the chlorine nuclear quadrupole hyperfine interaction, are observed. Kraitchman substitution coordinates, fits to the molecular moments of inertia, and \textit{ab initio} results are used to determine bond lengths and angles for the molecule of sufficient quality to be used in determining the structures of its complexes. \textit{Ab initio} calculations on the complexes of 2-chloro-1,1-difluoroethylene with argon and with hydrogen fluoride are used to assist in the analysis of spectra obtained in pulsed jet expansions of mixtures of 2-chloro-1,1-difluoroethylene with hydrogen fluoride in both argon and first run neon