Institute of Applied Radiation Chemistry, Lodz University of Technology, Zeromskiego 116, 90-924 Lodz, Poland.
Molecules. 2018 Nov 15;23(11):2981. doi: 10.3390/molecules23112981.
We have explored the theoretical applicability of adsorption on graphene for the isotopic enrichment of aromatic compounds. Our results indicate that for nonpolar molecules, like benzene, the model compound used in these studies shows a reasonable isotopic fractionation that is obtained only for the deuterated species. For heavier elements, isotopic enrichment might be possible with more polar compounds, e.g., nitro- or chloro-substituted aromatics. For benzene, it is also not possible to use isotopic fractionation to differentiate between different orientations of the adsorbed molecule over the graphene surface. Our results also allowed for the identification of theory levels and computational procedures that can be used for the reliable prediction of the isotope effects on adsorption on graphene. In particular, the use of partial Hessian is an attractive approach that yields acceptable values at an enormous increase of speed.
我们已经探索了在石墨烯上吸附对于芳香族化合物同位素富集的理论适用性。我们的结果表明，对于非极性分子，如苯，这些研究中使用的模型化合物显示出合理的同位素分馏，这种分馏仅在氘代物种中获得。对于较重的元素，更具极性的化合物，例如硝基或氯取代的芳烃，可能有可能进行同位素富集。对于苯，也不可能使用同位素分馏来区分吸附在石墨烯表面上的分子的不同取向。我们的结果还允许确定理论水平和计算程序，这些理论水平和计算程序可用于可靠地预测同位素对石墨烯吸附的影响。特别是，使用部分 Hessian 是一种很有吸引力的方法，它可以在速度大大提高的情况下获得可接受的值。
