A new two-dimensional Cd~II coordination polymer based on 2-(1H-imidazol-1-ylmethyl)-6-methyl-1H-benzimidazole and benzene-1,2-dicarboxylate: synthesis, crystal structure and characterization

摘要

In the construction of coordination polymers, many factors can influence the formation of the final architectures, such as the nature of the metal centres, the organic ligands and the counter-anions. In the coordination polymer poly[aqua-(mu-benzene-l,2-dicarboxylato-κ~4O~1,O~1':O~2,O~2')[mu-2-(1H-imidazol-1-ylmethyl)-6-methyl-1H-benzimidazole-κ~2N~2:N~3]cadmium(II)], [Cd(C_12H_12N_4)(C_8H_4O_4)-(H_2O)]_n or [Cd(immb)(1,2-bdic)(H_2O)]_n, each Cd~II ion is seven-coordinated by two N atoms from two symmetry-related 2-(1H-imidazol-1-ylmethyl)-6-methyl-1H-benzimidazole (immb) ligands, by four O atoms from two symmetry-related benzene-1,2-dicarboxylate (l,2-bdic~2-) ligands and by one water molecule, leading to a CdN_2O_5 distorted pentagonal bipyramidal coordination environment. The immb and l,2-bdic~2- ligands bridge CdII ions and form a two-dimensional network structure. O-H···O and N-H···O hydrogen bonds stabilize the structure. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviour and fluorescence properties of the title polymer have been investigated.