Research Initiative of Computational Sciences (RICS), Nanosystem Research Institute (NRI), National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan.
J Phys Chem B. 2013 Jun 6;117(22):6849-55. doi: 10.1021/jp403200j. Epub 2013 May 23.
Intermolecular interaction in the 1,2,5-chalcogenadiazole dimers was studied by ab initio molecular orbital calculations. Estimated CCSD(T) interaction energies for the thia-, selena- and tellura-diazole dimers are -3.14, -5.29, and -12.42 kcal/mol, respectively. The electrostatic and dispersion interactions are the major sources of the attraction in the dimers, although it was claimed that the orbital mixing (charge-transfer interaction) was the most prominent contribution to the stabilization. The induction (induced polarization) interaction also contributes largely to the attraction in the telluradiazole dimer. The large electrostatic and induction interactions are responsible for the strong attraction in the telluradiazole dimer. The short-range (orbital-orbital) interaction (sum of the exchange-repulsion and charge-transfer interactions) is repulsive. The directionality of the interactions increases in order of S < Se < Te. The electrostatic interaction is mainly responsible for the directionality. The strong directionality suggests that the chalcogen-nitrogen interaction plays important roles in controlling the orientation of molecules in those organic crystals. The nature of the chalcogen-nitrogen interaction in the chalcogenadiazole dimers is similar to that of the halogen bond, which is an electrostatically driven noncovalent interaction.
通过从头算分子轨道计算研究了 1,2,5-杂二氮杂苯二聚体的分子间相互作用。估算的硫代、硒代和碲代二唑二聚体的 CCSD(T)相互作用能分别为-3.14、-5.29 和-12.42 kcal/mol。静电相互作用和色散相互作用是二聚体吸引力的主要来源，尽管有人声称轨道混合（电荷转移相互作用）是稳定化的最主要贡献。诱导（感应极化）相互作用也大大促进了碲代二唑二聚体的吸引力。大的静电和诱导相互作用是碲代二唑二聚体强吸引力的原因。短程（轨道-轨道）相互作用（交换排斥和电荷转移相互作用的总和）是排斥的。相互作用的方向性按 S < Se < Te 的顺序增加。静电相互作用主要负责方向性。强方向性表明，杂氮-氮相互作用在控制这些有机晶体中分子的取向方面起着重要作用。杂二氮杂苯二聚体中杂氮-氮相互作用的性质与卤键相似，卤键是一种静电驱动的非共价相互作用。
