15min:

M. DEHGHANY, MAHIN AFSHARI, J. N. OLIAEE, N. MOAZZEN-AHMADI, Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4, CANADA; A. R. W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, CANADA.

Spectra of the weakly-bound N₂O-C₂H₂ and N₂O-C₂D₂ complexes in the region of the N₂O ₁ fundamental band (~2224 cm^-1) are observed in a pulsed supersonic slit jet expansion probed with a tunable diode laser. Two bands are analyzed for each complex: the fundamental (N-N stretch), and a combination involving the intermolecular torsional (out-of-plane bend) vibration. The resulting torsional frequencies are 44.37 and 40.01 cm^-1 for the C₂H₂ and C₂D₂ complexes, respectively. This represents the first observation of the N₂O-C₂D₂ isotopomer, and the first direct determination of an intermolecular frequency for nitrous oxide - acetylene.