title: Nitrous oxide dimer: observation of a new polar isomer.
abstract: Spectra of the nitrous oxide dimer (N2O)2 are studied in the region of the N2O nu1 fundamental band around 2230 cm-1 using a rapid-scan tunable diode laser spectrometer to probe a pulsed supersonic jet expansion. The previously known band of the centrosymmetric nonpolar dimer is analyzed in improved detail, and a new band is observed and assigned to a polar isomer of (N2O)2. This polar form of the dimer has a slipped parallel structure, rather similar to the slipped antiparallel structure of the nonpolar form but with a slightly larger intermolecular distance. The accurate rotational parameters determined here should enable a microwave observation of the polar N2O dimer. The need for a modern ab initio investigation of the N2O-N2O intermolecular potential energy surface is emphasized.
authors.affiliation: Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Dehghani
authors.forename: Mahin
authors.initials: M
authors.lastname: Afshari
authors.forename: Z
authors.initials: Z
authors.lastname: Abusara
authors.forename: N
authors.initials: N
authors.lastname: Moazzen-Ahmadi
authors.forename: A R W
authors.initials: AR
authors.lastname: McKellar