The C-O stretching band of the CO-N2O van der Waals complex

The weakly bound van der Waals complex CO-N2O has been studied for the first time. Absorption spectra in the CO stretching region near 2150 cm(-1) were recorded using a tunable diode laser spectrometer to probe the continuous supersonic jet from a slit-shaped nozzle. A total of 186 lines were measured and assigned as parallel (Delta K-a = 0) transitions of a planar near-prolate asymmetric top molecule. Analysis of these data with a conventional Hamiltonian yielded accurate values for the band origin, rotational, and centrifugal distortion parameters. The parameters obtained were very similar to those of the isoelectronic complex CO-CO2, indicating that CO-N2O has a similar T-shaped equilibrium structure. The effective intermolecular separation was determined to be 3.878 Angstrom. (C) 1996 Academic Press, Inc.