Rotational study on the van der Waals complex 1-chloro-1,1-difluoroethane-argon

Juan Wang; Junhua Chen; Gang Feng; Zhining Xia; Qian Gou

doi:10.1016/j.saa.2017.12.062

Rotational study on the van der Waals complex 1-chloro-1,1-difluoroethane-argon

Spectrochim Acta A Mol Biomol Spectrosc. 2018 Mar 15:193:447-450. doi: 10.1016/j.saa.2017.12.062. Epub 2017 Dec 21.

Authors

Juan Wang¹, Junhua Chen¹, Gang Feng¹, Zhining Xia¹, Qian Gou²

Affiliations

¹ Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
² Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China. Electronic address: qian.gou@cqu.edu.cn.

PMID: 29287280
DOI: 10.1016/j.saa.2017.12.062

Abstract

The rotational spectrum of the van der Waals complex formed between 1-chloro-1,1-difluoroethane and argon has been investigated by using a pulsed jet Fourier transform microwave spectrometer. Only one set of rotational transitions belonging to the lowest energy conformer has been observed and assigned, although theoretical calculations suggest six stable conformers that might be observed. The observed conformer, according to the experimental evidence from two isotopologues (³⁵Cl and ³⁷Cl), adopts a configuration in which the argon atom is located, close to the CF₂Cl top, between the CCF and CCCl planes (the dihedral angle ∠ArCCCl is 65.2°). The distance between argon atom and the center of mass of CH₃CF₂Cl is 3.949(2) Å. The dissociation energy, with pseudo diatomic approximation, is evaluated to be 2.4kJmol^-1.

Keywords: Argon; Freon; Pulsed jet; Rotational spectroscopy; Van der Waals interaction.