Rotational spectroscopy and molecular structure of the 1,1,2-trifluoroethylene-acetylene complex.
Rotational spectroscopy and molecular structure of the 1,1,2-trifluoroethylene-acetylene complex.
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1,1,2-三氟乙烯-乙炔络合物的旋转光谱和分子结构。
DOI：
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发表时间：
2008
影响因子：
4.4
通讯作者：
Vincent L. Chen
中科院分区：
文献类型：
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作者：
H. Leung;M. Marshall;Winn Cashion;Vincent L. Chen
在从头计算的指导下，获得了1，1，2-三氟乙烯与乙炔形成的络合物在6-22 GHz范围内的傅里叶变换微波旋转光谱，其中包括正常的同位异构体，在自然丰度下得到的四个单取代的~(13)C物种中的三个，以及使用商用的乙炔同位素品种，含有HCCD和H(13)C(13)CH的物种。尽管从头计算提出了两种可能的低能平面排列，但从光谱和使用Kraitchman[Am]确定的原子位置得出的旋转常数的组合分析，只得到了一个独特的结构。J.Phys.21，17(1953)]替换坐标。这种结构与CF(2)CHF[Single Bond]HF络合物的结构相似[H.O.Leung和M.D.Matt，J.Chem]。太棒了。126,114310(2007年)]，其中六氯甲烷分子与与CF(2)CHF的相同碳键合的F原子和H原子之间发生初级和次级相互作用。2.748(15)A氢键以乙炔为给体，1，1，2-三氟乙烯为受体，形成一个三点的104.49(15)°C[单键]功能点，以H角为中心。乙炔的pi键和与受体F原子配位的H原子之间的2.8694(9)A二次相互作用导致氢键偏离线性69.24(67)度。这种对线性的巨大偏离和两个分子间键长的相似性表明，这两个相互作用的重要性正在变得相当。
Guided by ab initio calculations, Fourier transform microwave rotational spectra in the 6-22 GHz region are obtained for the complex formed between 1,1,2-trifluoroethylene and acetylene, including the normal isotopomer, three of four singly substituted (13)C species obtained in natural abundance, and using commercially available isotopic varieties of acetylene, species containing HCCD and H(13)C(13)CH. Although the ab initio calculations suggest two possible low energy planar arrangements for the molecules in the complex, only a single, unique structure is obtained from a combined analysis of the rotational constants derived from the spectra and atomic positions determined using Kraitchman [Am. J. Phys. 21, 17 (1953)] substitution coordinates. This structure is similar to that obtained for the CF(2)CHF[Single Bond]HF complex [H. O. Leung and M. D. Marshall, J. Chem. Phys. 126, 114310 (2007)] in which both the primary and secondary interactions occur between the HCCH molecule and a F atom and a H atom bonded to the same carbon of CF(2)CHF. The 2.748(15) A hydrogen bond has acetylene as the donor and 1,1,2-trifluoroethylene as the acceptor and forms a 104.49(15) degrees C[Single Bond]Fcdots, three dots, centeredH angle. The 2.8694(9) A secondary interaction between the pi bond of acetylene and the H atom geminal to the acceptor F atom causes the hydrogen bond to deviate 69.24(67) degrees from linearity. This large deviation from linearity and the similarity of the two intermolecular bond lengths suggest that the two interactions are becoming comparable in importance.