Institute for Chemical Physics & Department of Chemistry, School of Science, State Key Laboratory of Electrical Insulation and Power Equipment, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
College of Chemical engineering & Technology, Department of Chemistry, Tianshui Normal University, Tianshui, 741001, China.
J Comput Chem. 2017 Apr 15;38(10):730-739. doi: 10.1002/jcc.24743. Epub 2017 Feb 6.
Noncovalent interactions involving aromatic rings, such as π···π stacking, CH···π are very essential for supramolecular carbon nanostructures. Graphite is a typical homogenous carbon matter based on π···π stacking of graphene sheets. Even in systems not involving aromatic groups, the stability of diamondoid dimer and layer-layer graphane dimer originates from C - H···H - C noncovalent interaction. In this article, the structures and properties of novel heterogeneous layer-layer carbon-nanostructures involving π···H-C-C-H···π···H-C-C-H stacking based on [n]-graphane and [n]-graphene and their derivatives are theoretically investigated for n = 16-54 using dispersion corrected density functional theory B3LYP-D3 method. Energy decomposition analysis shows that dispersion interaction is the most important for the stabilization of both double- and multi-layer-layer [n]-graphane@graphene. Binding energy between graphane and graphene sheets shows that there is a distinct additive nature of CH···π interaction. For comparison and simplicity, the concept of H-H bond energy equivalent number of carbon atoms (noted as NHEQ), is used to describe the strength of these noncovalent interactions. The NHEQ of the graphene dimers, graphane dimers, and double-layered graphane@graphene are 103, 143, and 110, indicating that the strength of C-H···π interaction is close to that of π···π and much stronger than that of C-H···H-C in large size systems. Additionally, frontier molecular orbital, electron density difference and visualized noncovalent interaction regions are discussed for deeply understanding the nature of the C-H···π stacking interaction in construction of heterogeneous layer-layer graphane@graphene structures. We hope that the present study would be helpful for creations of new functional supramolecular materials based on graphane and graphene carbon nano-structures. © 2017 Wiley Periodicals, Inc.
非共价相互作用涉及芳香环，如π···π 堆积、CH···π 等，对于超分子碳纳米结构非常重要。石墨是一种典型的同质碳物质，基于石墨烯片的 π···π 堆积。即使在不涉及芳基基团的系统中，类金刚石二聚体和层状石墨烷二聚体的稳定性也源于 C−H···H−C 非共价相互作用。在本文中，使用色散修正密度泛函理论 B3LYP-D3 方法，对涉及π···H-C-C-H···π···H-C-C-H 堆积的新型异质层状碳纳米结构的结构和性质进行了理论研究，这些结构基于[n]-石墨烷和[n]-石墨烯及其衍生物，n = 16-54。能量分解分析表明，色散相互作用对于双层和多层[n]-石墨烷@石墨烯的稳定化是最重要的。石墨烷和石墨烯片之间的结合能表明 CH···π 相互作用具有明显的加和性。为了比较和简化，使用 H-H 键等效碳原子数的概念（记为 NHEQ）来描述这些非共价相互作用的强度。石墨烯二聚体、石墨烷二聚体和双层石墨烷@石墨烯的 NHEQ 分别为 103、143 和 110，表明 C-H···π 相互作用的强度接近于π···π 相互作用，并且在大尺寸体系中比 C-H···H-C 相互作用强得多。此外，讨论了前沿分子轨道、电子密度差和可视化非共价相互作用区域，以深入了解构建异质层状石墨烷@石墨烯结构中 C-H···π 堆积相互作用的性质。我们希望本研究有助于基于石墨烷和石墨烯碳纳米结构的新型功能超分子材料的创造。© 2017 威利期刊公司
