title: Detection of a higher energy isomer of the CO-N2O van der Waals complex and determination of two of its intermolecular frequencies.
abstract: Infrared spectra in the carbon monoxide CO stretch region (∼2150 cm-1) and in the ν3asymmetric stretch region of N2O (∼2223 cm-1) are assigned to the previously unobserved O-bonded form of the CO-N2O dimer ("isomer 2"). This van der Waals complex has a planar skewed T-shaped structure like that of the previously observed C-bonded form ("isomer 1"), but with the CO rotated by 180°. The effective intermolecular distance between the centers of mass is 3.51 Å for isomer 2 as compared to 3.88 Å for isomer 1. In addition to the fundamental band, two combination bands are observed for isomer 2, yielding values for two intermolecular vibrational modes: 14.502(5) cm-1for the coupled disrotatory motion or the uncoupled CO rock and 21.219(5) cm-1for the out-of-plane rock. We show that the published ab initio study on this system is inadequate in predicting the intermolecular frequencies for isomer 2 of CO-N2O.
authors.affiliation: Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4, Canada. nmoazzen@ucalgary.ca.
authors.forename: A J
authors.initials: AJ
authors.lastname: Barclay
authors.affiliation: Institute of Condensed Matter and Nanosciences (IMCN), Université catholique de Louvain, Louvain-la-Neuve, Belgium. clement.lauzin@uclouvain.be.
authors.forename: C
authors.identifier: http://orcid.org/0000-0001-5044-5137
authors.initials: C
authors.lastname: Lauzin
authors.affiliation: Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4, Canada. nmoazzen@ucalgary.ca.
authors.forename: S
authors.initials: S
authors.lastname: Sheybani-Deloui
authors.affiliation: Natural Resources Canada, CanmetENERGY in Devon, 1 Oil Patch Drive, Suite A202, Devon, Alberta T9G 1A8, Canada.
authors.forename: K H
authors.initials: KH
authors.lastname: Michaelian
authors.affiliation: Department of Physics and Astronomy, University of Calgary, 2500 University Drive North West, Calgary, Alberta T2N 1N4, Canada. nmoazzen@ucalgary.ca.
authors.forename: N
authors.initials: N
authors.lastname: Moazzen-Ahmadi