Syntheses, Structural Evolutions, and Properties of Cd(II) Coordination Polymers Induced by Bis(pyridyl) Ligand with Chelated or Protonated Spacer and Diverse Counteranions

Hydrothermal reaction of Cd(II) metal salts, diverse organic acids, as well as flexible bis(pyridyl) ligand leads to the formation of 10 complexes, namely, [Cd2LCl4] (1), [Cd(H2L)(SO4)(2)(H2O)(2)](n)center dot 6nH(2)O (2), [CdL(malonate)](n)center dot 5nH(2)O (3), [Cd2L(malonate)Cl-2(H2O)](n)center dot nH(2)O (4), [Cd-2(H2L)(succinate)(3)](n)center dot 4nH(2)O (5), [Cd2L(fumarate)(2)(H2O)(2)](n)center dot 2nH(2)O (6), [Cd2L(m-BDC2-)(2)](n)center dot 2nH(2)O (7), [Cd-2(L)(p-BDC2-)(2)(H2O)(3)](n)center dot 3nH(2)O (8), [Cd-3(L)(2)(p-BDC2-)(3)(H2O)(n)center dot nH(2)O (9), and [Cd-3(H2L)(p-BDC2-)(2) (SO4)(2)(H2O)(3)](n)center dot 2nH(2)O (10) (L = N,M-bis(pyridin-3-ylmethyl)ethane-1,2diamine, m-BDC2- = m -benzene dicarboxylate dianion, P-BDC2- = p -benzene dicarboxylate dianion), which have been characterized by elemental analysis, infrared, thermogravimetric analysis, PL, powder and single-crystal X-ray diffraction: Structural analyses indicate that the diverse coordination modes of the bis(pyridyl) ligand with a chelated or protonated spacer, the feature of different inorganic and organic anions, can effectiyely influence the topological Structures of these complexes. Complex 1 presents a three-dimensional (3D) hybrid network which is accomplished by the interconnection of adjacent Cd(II) cations through L molecules and mu(2)-Cl- anions. Complex 2 exhibits an interesting pseudo 2-fold interpenetrated network formed by the interconnection of.a [Cd-H2L2+] pcu net and [SO42+ -H2O](n) pcu net. In complexes 3 and 4, adjacent Cd(II) cations are all bridged by dicarboxylate and L to generate a sill layer. In contrast, complex 5 presents 3-fold parallel interpenetrated sql layer owing to the protonated spacer of H2L2+ cation which extends, the size of the quadrate window. The organic dicarboxylates in complexes 6 and 7 present more -abundant coordination modes which join adjacent Cd(II) cations;together with, L molecules, thus giving rise to a different 3D framework with sra and-snk topology. The p-BDC2- dianions in complexes 8, 9, and 10 present different coordination modes and join adjacent Cd(II) cations together with t molecules and H2L2+ cations to frirm a diverse ladder chain, tfc and new (4(4).6(11))(6(6)) topology. Luminescent investigation reveals that the emiSsion maximum of these 10 complexes varies from 376 to 450 nm.