Straining to Put the Pieces Together: The Molecular Structure of ( E )-1-Chloro-1,2-difluoroethylene–Acetylene from Microwave Spectroscopy
Straining to Put the Pieces Together: The Molecular Structure of ( E )-1-Chloro-1,2-difluoroethylene–Acetylene from Microwave Spectroscopy
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努力将各个部分拼凑在一起：微波光谱法中 (E)-1-氯-1,2-二氟乙烯·乙炔的分子结构
DOI：
10.1021/acs.jpca.1c05169
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Mlaver, Eli
中科院分区：
文献类型：
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作者：
Leung, Helen O.;Marshall, Mark. D.;Mlaver, Eli
用宽带啁啾脉冲和窄带Balle-Flygare傅里叶变换微波谱仪测量了乙炔和(E)-1-氯-1，2-二氟乙烯形成的气相杂二聚体在5.6~19.7 GHz的微波转动光谱。通过分析配合物和三个同位素取代物种的正常同位素的光谱获得的旋转常数确定了配合物的结构：在自然丰度中获得的单一取代的37Cl同位素，以及使用同位素浓缩的HC13CH样品获得的两个单独取代13C的同位素。乙炔与单一卤化碳上的氟原子形成氢键，并与同一碳上的氢原子形成二次相互作用。形成二次相互作用时产生的角应变被氢键对氟有利的静电性所抵消。与1，1，2-三氟乙烯和顺-1，2-二氟乙烯的乙炔络合物的比较表明，远端碳上的卤素取代对该键基序的影响。
The microwave, rotational spectrum between 5.6 and 19.7 GHz of the gas-phase heterodimer formed between acetylene and (E)-1-chloro-1,2-difluoroethylene is obtained using both broadband, chirped-pulse and narrow band, Balle–Flygare Fourier transform microwave spectrometers. The structure of the complex is determined from the rotational constants obtained via the analysis of the spectra for the normal isotopologue of the complex and three isotopically substituted species: the singly substituted37Cl isotopologue, obtained in natural abundance, and two isotopologues singly substituted with13C, obtained using an isotopically enriched HC13CH sample. The acetylene forms a hydrogen bond with the fluorine atom on singly halogenated carbon and a secondary interaction with the hydrogen atom on that same carbon. The angle strain induced in forming the secondary interaction is offset by the favorable electrostatics of the hydrogen bond to fluorine. Comparisons with acetylene complexes of 1,1,2-trifluoroethylene andcis-1,2-difluoroethylene show the effects of halogen substitution at the remote carbon on this bonding motif.