Four Three-Dimensional Coordination Polymers Constructed by 2-((1H-1,2,4-Triazol-1-yl)methyl)-1H-Imidazole-4,5-Dicarboxylate: Syntheses, Topological Structures, and Magnetic Properties

Hydrothermal reactions of Mn­(II), Co­(II), Cu­(II), and Cd­(II) salts with 2-((1H-1,2,4-triazol-1-yl)­methyl)-1H-imidazole-4,5-dicarboxylic acid (H3tmidc) lead to four novel coordination polymers, namely, [Mn3(tmidc)2(H2O)4]·(H2O)6 (1), [Co3(tmidc)2(H2O)4]·(H2O)4 (2), [Cu3(tmidc)2(H2O)]·(H2O) (3), and [Cd­(Htmidc)] (4). Compound 1 has a three-dimensional (3D) architecture, and the topological study shows that its framework features a 3D (3,4)-connected fsc-3,4-Pbca network with the Schläfli topological symbol of (63)­(63.83). Compound 2 exhibits a 3D pillared framework constructed by 4-fold one-dimensional (1D) helical chains and possesses open helical channels in the framework. Topological analysis reveals that it is a unique (3,4)-connected net with the Schläfli symbol of (4.52)­(4.5.114) which is not enumerated in RCSR andTOPOS, and has not been reported in the literature. Compound 3 features a 3D intricate framework displaying a new (3,4)-connected 4-nodal net with the Schläfli symbol of (5.72)­(4.5.7)­(52.72.8.10)­(4.5.73.8) which has not been observed in any other coordination polymers. Topological analysis of the 3D network found in compound 4 reveals that the whole structure can be rationalized as a (4.65)­(4.65) crb topological net.