Synthesis, Crystal Structure, and Photoluminescence of Coordination Polymers with Mixed Ligands and Diverse Topologies

This work presents systematic investigation on reactions of zinc(II) salts with a rigid tripodal ligand in the presence of different benzenedicarboxylic acids. Seven new coordination polymers [Zn(tib)(1,3-BDC)]·H 2 O ( 1 ), [Zn 2 (tib)(1,3-BDC) 2 (H 2 O)]·2H 2 O ( 2 ), [Zn 2 (tib)(1,2-BDC)Cl 2 ] ( 3 ), [Zn 4 (tib) 2 (1,2-BDC) 4 ]·2H 2 O ( 4 ), [Zn 2 (tib) 2 (1,2-BDC)](NO 3 ) 2 ( 5 ), [Zn 2 (tib) 2 (1,2-BDC)]I 2 ( 6 ), and [Zn 3 (tib) 2 (4-BPA)Cl 4 ]·2H 2 O ( 7 ) [tib = 1,3,5-tris(1-imidazolyl)benzene, 1,3-BDC 2− = 1,3-benzenedicarboxylate, 1,2-BDC 2− = 1,2-benzenedicarboxylate, 4-BPA 2− = 4-bromo-1,2-benzenedicarboxylate] were obtained, and they were characterized by single crystal X-ray diffraction, IR, thermogravimetric and elemental analyses. Complexes 1, 4, and 7 are two-dimensional (2D) networks containing infinite one-dimensional (1D) Zn(II)-tib chains linked together by auxiliary dicarboxylate ligands. Complexes 2 with 2-fold interpenetration and 3 are three-dimensional (3D) frameworks containing infinite 2D networks pillared by 1,2-BDC 2− ligands, while 5 and 6 feature unusual 3D supramolecular architectures with 4.8 2 networks linked by 1,2-BDC 2− ligands. The results showed that the dicarboxylate auxiliary ligands and the counteranions have a great influence on the structure of the complexes. The luminescence properties of 1 − 7 in the solid state were studied.