Yuge Tetsuharu, Tohnai Norimitsu, Fukuda Takeyoshi, Hisaki Ichiro, Miyata Mikiji
Department of Material and Life Science, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
Chemistry. 2007;13(15):4163-8. doi: 10.1002/chem.200700099.
Hierarchical classification and single-crystal X-ray analysis of unique pseudo-cubic hydrogen-bond networks composed of primary ammonium carboxylates were carried out. The networks consist of four carboxylate anions and four primary ammonium cations at the corners of the cube, and twelve charge-assisted N--H...O hydrogen bonds on the sides of the cube. The configuration of the carboxylate anions generates topological diversity in the network. The results of this hierarchical classification showed that pseudo-cubic hydrogen-bond networks composed of primary ammonium carboxylates can form nine topologically different networks. These pseudo-cubic networks are a subset of the networks formed by octameric water in the form of an "ice cube". The classification system can be applied to other pseudo-cubic networks in a similar way. A survey of crystal structures based on combinations of triphenylacetic acid with various alkylamines (carbon numbers up to eight) and examination of the CSD (Cambridge Structural Database) showed eight salts that form such networks in their crystal structures. These structures are classified into six topologically different networks. Similar networks composed of other salts are also discussed from a topological point of view.
对由伯铵羧酸盐组成的独特伪立方氢键网络进行了层次分类和单晶X射线分析。该网络由位于立方体角上的四个羧酸根阴离子和四个伯铵阳离子组成，以及位于立方体边上的十二个电荷辅助的N-H...O氢键。羧酸根阴离子的构型在网络中产生了拓扑多样性。这种层次分类的结果表明，由伯铵羧酸盐组成的伪立方氢键网络可以形成九个拓扑不同的网络。这些伪立方网络是以“冰块”形式的八聚体水形成的网络的一个子集。该分类系统可以以类似的方式应用于其他伪立方网络。基于三苯乙酸与各种烷基胺（碳原子数最多为八个）的组合对晶体结构进行的调查以及对剑桥结构数据库（CSD）的检查表明，有八种盐在其晶体结构中形成了这样的网络。这些结构被分类为六个拓扑不同的网络。还从拓扑角度讨论了由其他盐组成的类似网络。
