Infrared spectra of both isomers of CO2-CO in the CO2v3 region. (18th June 2021)

• Record Type: Journal Article
• Authors: Wakwella, P.; McKellar, A.R.W.; Moazzen-Ahmadi, N.
• Is Part Of: Molecular physics. Volume 119:Number 12(2021)
• Publication Date: 2021-06-18
• Subjects: Carbon dioxide -- carbon monoxide -- molecular complex -- infrared -- vibrational bands; Molecules -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Molécules -- Périodiques; Chimie physique et théorique -- Périodiques; 539.6.05
• DOI: 10.1080/00268976.2021.1936251
• Languages: English
• ISSNs: 0026-8976

Abstract

Abstract : Extensive infrared spectra of the weakly-bound CO2 -CO dimer are observed in the carbon dioxide ν3 asymmetric stretch region (≈2350 cm −1 ) using a tunable infrared OPO laser source to probe a pulsed slit jet supersonic expansion. Both C-bonded and O-bonded isomers are analysed for the normal isotopologue as well as for 13 CO2 -CO and 16 O 13 C 18 O-CO, the latter being the first observation of an asymmetrically substituted form for which all values of Ka are allowed. Combination bands involving the lowest in-plane intermolecular bending modes are also studied for both isomers. Weak bands near 2337 cm −1 are assigned to CO2 hot band transitions ( v 1, v 2 l 2, v 3 ) = (01 1 1) ← (01 1 0), yielding the splitting of the degenerate CO2 ν2 bend into in-plane and out-of-plane components due to the presence of the CO. This splitting has rather different values for the C- and O- bonded isomers, 4.57 and 1.59 cm −1, respectively, with the out-of-plane mode higher in energy than the in-plane for both cases. GRAPHICAL ABSTRACT: UF0001