College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University , Wenhua East Road 88, Jinan, Shandong 250014, P. R. China.
J Phys Chem A. 2013 Oct 24;117(42):10944-50. doi: 10.1021/jp407890t. Epub 2013 Oct 10.
Recently, Legon et al. reported the first generation and characterization of H2O/H2S···AgCl complexes by rotational spectroscopy and proposed whether there is a silver bond analogous to the more familiar hydrogen and halogen bonds. In this study, a theoretical investigation was performed to answer this question and to deepen the nature of intermolecular interactions for H2O/H2S···M-Cl (M = Cu, Ag, and Au) complexes. NBO analyses reveal that two types of delocalization interactions coexist in these complexes. Apart from the expected σ-donation interaction, the hyperconjugation interaction between H2O/H2S and M-Cl also takes part in the bonding. On the basis of such a dual-bonding mechanism, one class of bond, termed Cu/Ag bond, was defined in this study. In addition, the topological properties at a bond critical point, binding energies, and stretching frequency shifts studied here support that Cu/Ag bond is a sister bond to Au bond put forward previously by Sadlej et al. The Cu/Ag/Au bond is partially covalent and partially electrostatic in nature. Finally, the dual-bonding mechanism of Cu/Ag/Au bond was further discussed. This dual-bonding scheme may be considered a new synergistic bonding model for coordination compounds.
最近，Legon 等人通过旋转光谱学报告了第一代 H2O/H2S···AgCl 配合物的生成和特性，并提出是否存在类似于更熟悉的氢键和卤键的银键。在这项研究中，进行了理论研究来回答这个问题，并深入研究 H2O/H2S···M-Cl（M = Cu、Ag 和 Au）配合物的分子间相互作用的性质。NBO 分析表明，这两种类型的离域相互作用共存于这些配合物中。除了预期的 σ-给体相互作用外，H2O/H2S 与 M-Cl 之间的超共轭相互作用也参与了成键。基于这种双重键合机制，本研究定义了一类键，称为 Cu/Ag 键。此外，本文研究的键临界点的拓扑性质、结合能和伸缩频率位移支持了 Sadlej 等人之前提出的 Au 键与 Cu/Ag 键是姊妹键的观点。Cu/Ag/Au 键本质上部分是共价键，部分是静电键。最后，进一步讨论了 Cu/Ag/Au 键的双重键合机制。这种双重键合方案可以被认为是配位化合物的一种新协同键合模型。
