Position-specific 13C fractionation during liquid-vapor transition is correlated to the strength of intermolecular interaction in the liquid phase
Position-specific 13C fractionation during liquid-vapor transition is correlated to the strength of intermolecular interaction in the liquid phase
复制标题
液-汽转变过程中位置特异性 13C 分馏与液相中分子间相互作用的强度相关
DOI：
10.1021/acs.jpcb.7b00971
复制
发表时间：
2017
期刊：
影响因子：
--
通讯作者：
J. Parinet and G. S. Remaud
中科院分区：
文献类型：
--
作者：
M. Julien;P. Hohener;R. J. Robins;J. Parinet and G. S. Remaud
研究了在蒸馏过程中观察到的位置特定的~(13)C分馏与液体中分子间相互作用强度的关系。一系列在模式和强度方面表现出不同分子间相互作用的分子被纳入研究。尽管以前有人提出在蒸发过程中，与蒸汽交界的薄液层中的13C同位素扩散效应不是位置特定的，但在这里我们证明了情况并非如此。特别是，对一系列醇类化合物显示了位置特异性效应。我们的假设是，液态中的分子间相互作用是在分子上观察到的位置特定的13C分馏的来源。含有化学功能杂原子的碳的~(13)C同位素效应与相对介电常数、溶剂氢键酸度和溶剂氢键碱性之间有明显的趋势，而当使用全分子的~(13)C含量时，只有微弱的趋势。此外，当使用氢键酸度参数进行关联时，通过区分H-受体和H-给体分子，出现了两类产物。这有力地支持了13C在靠近相互作用中心的位置上发挥重要作用的假设。
The relationship between the strength of the intermolecular interaction in liquid and the position-specific13C fractionation observed during distillation was investigated. A range of molecules showing different intermolecular interactions in terms of mode and intensity were incorporated in the study. Although it had previously been suggested that during evaporation the diffusive13C isotope effect in the thin liquid layer interfaced with vapor is not position-specific, herein we show that this is not the case. In particular, the position-specific effect was demonstrated for a series of alcohols. Our hypothesis is that intermolecular interactions in the liquid phase are the source of position-specific13C fractionation observed on the molecule. A clear trend is observed between the13C isotope effect of the carbon bearing the heteroatom of chemical function and the relative permittivity, the solvent hydrogen bond acidity, and the solvent hydrogen bond basicity, while only a weak trend was observed when using the13C content of the whole molecule. Furthermore, two families of products appeared when using the hydrogen bond acidity parameter for the correlation by distinguishing H-acceptor and H-donor molecules from those H-acceptors only. This strongly reinforces the hypothesis of an important role of the13C positioned close to the interaction center.