Fundamental Vibrational Frequencies and Spectroscopic Constants of cis- and trans-HOCS, HSCO, and Isotopologues via Quartic Force Fields

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• 作者：Ryan C. Fortenberry ; Xinchuan Huang ; Michael C. McCarthy ; T. Daniel Crawford ; Timothy J. Lee
• 刊名：Journal of Physical Chemistry B
• 出版年：2014
• 出版时间：June 19, 2014
• 年：2014
• 卷：118
• 期：24
• 页码：6498-6510
• 全文大小：273K
• 年卷期：v.118,no.24(June 19, 2014)
• ISSN：1520-5207

文摘

Highly accurate, coupled-cluster-based quartic force fields (QFFs) have been employed recently to provide spectroscopic reference for a myriad of molecules. Here, we are extending the same approach to provide vibrational and rotational spectroscopic reference data for the sulfur analogues of HOCO, HSCO, and HOCS, in both the cis and trans conformations as well as the D and ³⁴S isotopologues of each system. The resulting energies corroborate previous computations showing that trans-HSCO is the lowest-energy isomer for this system. The vibrational frequencies are computed with both second-order vibrational perturbation theory (VPT2) and vibrational configuration interaction (VCI) methods. The VPT2 and VCI QFF frequencies largely agree with one another to better than 5.0 cm^鈥? (often better than 1.0 cm^鈥?) and are also consistent with the type of behavior exhibited in previous studies. As such, the reference data provided here should assist in analysis of environments in which these sulfur systems may be found, including the interstellar medium, combustion flames, or laboratory simulations of either.