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The insensitivity of the moments of inertia to certain geometric parameters for the limited set of isotopologues studied led to unexpected results for a preliminary structure of the complex formed between 1-chloro-1-fluoroethylene and acetylene presented three years ago.$ OSU International Symposium on Molecular Spectroscopy, Talk RG10 (2007)} The availability of this chlorofluoroethylene with a single deuterium substitution in both (\textit{E}) and (\textit{Z}) isomeric forms allows us to supplement the original data set with microwave spectra of (\textit{E})-CHDC$\mathrm{<mrow\; data-mjx-texclass="ORD">35</mrow>}$ClF--HCCH and (\textit{Z})-CHDC$\mathrm{<mrow\; data-mjx-texclass="ORD">35</mrow>}$ClF--HCCH. Supported by the results of \textit{ab initio} calculations, a planar, chemically reasonable structure is obtained for this complex, in which the acetylene forms a hydrogen bond with the fluorine atom of 1-chloro-1-fluoroethylene. The hydrogen bond bends to allow a secondary interaction with the hydrogen atom \textit{cis} to this fluorine atom. Comparisons with the structure of the analogous complexes formed with vinyl fluoride and 1,1-difluoroethylene reveal the effects of chlorine substitution geminal to the acceptor atom of the hydrogen bond.