Weakly-bound clusters of atmospheric molecules: infrared spectra and structural calculations of (CO$_2$)$_n$-(CO)$_m$-(N$_2$)$_p$, $(n, m, p)$ = (2, 1, 0), (2, 0, 1), (1, 2, 0), (1, 0, 2), (1, 1, 1), (1, 3, 0), (1, 0, 3), (1, 2, 1), (1, 1, 2)

A. J. Barclay; A. R. W. McKellar; A. Pietropolli Charmet; N. Moazzen-Ahmadi

doi:10.1039/D2CP00263A

paper

Weakly-bound clusters of atmospheric molecules: infrared spectra and structural calculations of (CO $_{2}$ ) $_{n}$ -(CO) $_{m}$ -(N $_{2}$ ) $_{p}$ , $(n, m, p)$ = (2, 1, 0), (2, 0, 1), (1, 2, 0), (1, 0, 2), (1, 1, 1), (1, 3, 0), (1, 0, 3), (1, 2, 1), (1, 1, 2)

arXiv:2202.13233 · doi:10.1039/D2CP00263A

Abstract

Structural calculations and high-resolution infrared spectra are reported for trimers and tetramers containing CO $_{2}$ together with CO and/or N $_{2}$ . Among the 9 clusters studied here, only (CO $_{2}$ ) $_{2}$ -CO was previously observed by high-resolution spectroscopy. The spectra, which occur in the region of the $ν_{3}$ fundamental of CO $_{2}$ (~2350 cm $^{- 1}$ ), were recorded using a tunable optical parametric oscillator source to probe a pulsed supersonic slit jet expansion. The trimers (CO $_{2}$ ) $_{2}$ -CO and (CO $_{2}$ ) $_{2}$ -N $_{2}$ have structures in which the CO or N $_{2}$ is aligned along the symmetry axis of a staggered side-by-side CO $_{2}$ dimer unit. The observation of two fundamental bands for (CO $_{2}$ ) $_{2}$ -CO and (CO $_{2}$ ) $_{2}$ -N $_{2}$ shows that this CO $_{2}$ dimer unit is non-planar, unlike (CO $_{2}$ ) $_{2}$ itself. For the trimers CO $_{2}$ -(CO) $_{2}$ and CO $_{2}$ -(N $_{2}$ ) $_{2}$ , the CO or N $_{2}$ monomers occupy equivalent positions in the 'equatorial plane' of the CO $_{2}$ , pointing toward its C atom. To form the tetramers CO $_{2}$ -(CO) $_{3}$ and CO $_{2}$ -(N $_{2}$ ) $_{3}$ , a third CO or N $_{2}$ monomer is then added off to the 'side' of the first two. In the mixed tetramers CO $_{2}$ -(CO) $_{2}$ -N $_{2}$ and CO $_{2}$ -CO-(N $_{2}$ ) $_{2}$ , this 'side' position is taken by N2 and not CO. In addition to the fundamental bands, combination bands are also observed for (CO $_{2}$ ) $_{2}$ -CO, CO $_{2}$ -(CO) $_{2}$ , and CO $_{2}$ -(N $_{2}$ ) $_{2}$ , yielding some information about their low-frequency intermolecular vibrations.

35 pages, 7 figures and 4 tables

References in corpus (1)

Spectra of CO2-N2 dimer in the 4.2 micron region: symmetry breaking of the intramolecular CO2 bend, the intermolecular bend and higher K-values for the fundamental

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Infrared spectra of (CO $_{2}$ ) $_{2}$ -Rg trimers, Rg = Ne, Ar, Kr, and Xe

Weakly-bound clusters of atmospheric molecules: infrared spectra and structural calculations of (CO2​)n​-(CO)m​-(N2​)p​, (n,m,p) = (2, 1, 0), (2, 0, 1), (1, 2, 0), (1, 0, 2), (1, 1, 1), (1, 3, 0), (1, 0, 3), (1, 2, 1), (1, 1, 2)

Abstract

References in corpus (1)

Cited by in corpus (1)

Weakly-bound clusters of atmospheric molecules: infrared spectra and structural calculations of (CO $_{2}$ ) $_{n}$ -(CO) $_{m}$ -(N $_{2}$ ) $_{p}$ , $(n, m, p)$ = (2, 1, 0), (2, 0, 1), (1, 2, 0), (1, 0, 2), (1, 1, 1), (1, 3, 0), (1, 0, 3), (1, 2, 1), (1, 1, 2)