High-Resolution Infrared Diode Laser Spectroscopy of Ne-N2O, Kr-N2O, and Xe-N2O.

The rotationally resolved spectra of the van der Waals complexes Ne-N2O, Kr-N2O, and Xe-N2O have been investigated in the region of the nu3 N2O monomer vibrational band using a diode laser absorption spectrometer that is incorporated with a multipass cell and a pulsed jet. The spectra of these three complexes are completely analyzed using a normal asymmetric rotor Hamiltonian, and the effective molecular constants are accurately determined for both the ground and the excited vibrational states. These results show that, like Ar-N2O, the complexes have a T-shaped configuration in which the rare gas atom prefers to lie near to the oxygen side of N2O. The band origins of Rg-N2O (Rg = Ne, Ar, Kr, and Xe) are observed to shift by 0.36125, 0.15038, -0.10131, and -0.49066 cm-1 from that of the monomer, respectively. These band origin shifts are well explained by a simple model for the intermolecular potential. Copyright 1998 Academic Press