Planar Layer-Stacking of CHON-Containing Molecules

Understanding the relationship between the molecular structure and crystal packing is fundamental while challenging crystal engineering. Planar layer-stacking structures have attracted widespread attention for their potential to enhance the charge transport performance of organic semiconductors and reduce the sensitivity of energetic molecules. Still, it lacks insights into such stacking. We conduct in this work a comprehensive understanding of 65 planar layer-stacked CHON-containing molecules based on intermolecular interaction. All the 59 hydrogenous molecules each always form HB in crystal packing, ascribed to the H atoms possessing the largest positive electrostatic potential extremes, and it requires negative ones against them to enhance intermolecular attraction and consolidate the planar layers. Meanwhile, the intralayer intermolecular interaction strength is not a decisive factor of the planar layer-stacking for either H-free or hydrogenous molecules, and its dependence on interlayer distance or packing coefficient is found, even though there seemingly exist some rough trends. It seems that we can hardly understand the planar layer-stacking based on CHON-containing alone, and further study covering other compositions is required.