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C···S Tetrel Bond Favored in the Phenyl Isothiocyanate-CO2 Complex: A Rotational Study
Siyu Zou1, Juncheng Lei1, Tianyue Gao1
1Department of Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Daxuecheng South Rd. 55, 401331 Chongqing, China.
Abstract:
The rotational spectrum of the phenyl isothiocyanate-CO2 complex was investigated by pulsed-jet Fourier transform microwave spectroscopy complemented by quantum chemical calculations. Only one isomer, with CO2 almost in the plane of phenyl isothiocyanate, has been detected in the pulsed jet, of which the spectrum displays a quadrupole coupling hyperfine structure due to the presence of a 14N nucleus (I = 1). This structure is nearly equal to the lowest energy geometry obtained by B3LYP-D3(BJ)/6-311++G(d,p), which has been dominated by a C···S tetrel bond (n → π* interaction) and one secondary C-H···O hydrogen bond (n → σ* interaction). Molecular electrostatic potential and natural bond orbital analysis were used to characterize the noncovalent interactions of the complex. The results from this study would lay the groundwork for the design and advancement of materials that exhibit high efficiency in capturing CO2.
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