Herein, we present a study of the short contacts that several heterocycles of the same family, namely, succinic and maleic anhydrides, maleimide, and succinimide establish in their condensed phases. DFT calculations on model systems in the gas phase have allowed us to calibrate the strength of such interactions, obtaining associated energies up to 2 kcal/mol. We have performed MEP and EDA analysis to unveil their nature, which is mainly electrostatic with some London dispersion contribution. Furthermore, the origin of the interaction is the existence of a charge depletion region (a π-hole) in the inner part of the rings. This hole interacts with a Lewis base in a precise topological way, with the contacts showing a high directionality as revealed by the analysis of hundreds of crystal structures. We believe that the description for the first time of these interactions, along with their abundance, can assist their use as a tool in crystal design.

中文翻译：

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琥珀酸和马来酸酐衍生物中的非共价相互作用

在这里，我们提出了对短接触的研究，该短接触是同一家族的几个杂环，即琥珀酸和马来酸酐，马来酰亚胺和琥珀酰亚胺在它们的缩合相中建立的。在气相模型系统上的DFT计算使我们能够校准这种相互作用的强度，获得高达2 kcal / mol的相关能量。我们已经执行了MEP和EDA分析以揭示它们的性质，该性质主要是静电，并且在伦敦具有一定的色散贡献。此外，相互作用的起源是在环的内部存在电荷耗尽区（π孔）。通过对数百种晶体结构的分析可以看出，该孔以精确的拓扑方式与Lewis碱相互作用，并显示出较高的方向性。