Self-assembly of three cadmium(II) complexes based on 5-methylisophthalic acid and flexible bis(imidazole) ligands with different spacer lengths

Influence of ligand composition on crystal structure formation – isostructurality and morphotropism

The replacement of an H-atom with a Me-group leads to the isostructurality of polymeric Ag(i) complexes, whereas it causes morphotropic adjustments in the parent ligands (discrete molecules).

Cd(II) and Co(II) coordination polymers constructed from benzene-1,4-dicarboxylic acid and 2-(pyridin-3-yl)-1H-benzimidazole ligands

In poly[aqua(μ3-benzene-1,4-dicarboxylato-κ(5)O(1),O(1'):O(1):O(4),O(4'))[2-(pyridin-3-yl-κN)-1H-benzimidazole]cadmium(II)], [Cd(C8H4O4)(C12H9N3)(H2O)]n, (I), each Cd(II) ion is seven-coordinated by the pyridine N atom from a 2-(pyridin-3-yl)benzimidazole (3-PyBIm) ligand, five O atoms from three benzene-1,4-dicarboxylate (1,4-bdc) ligands and one O atom from a coordinated water molecule. The complex forms an extended two-dimensional carboxylate layer structure, which is further extended into a three-dimensional network by hydrogen-bonding interactions. In catena-poly[[diaquabis[2-(pyridin-3-yl-κN)-1H-benzimidazole]cobalt(II)]-μ2-benzene-1,4-dicarboxylato-κ(2)O(1):O(4)], [Co(C8H4O4)(C12H9N3)2(H2O)2]n, (II), each Co(II) ion is six-coordinated by two pyridine N atoms from two 3-PyBIm ligands, two O atoms from two 1,4-bdc ligands and two O atoms from two coordinated water molecules. The complex forms a one-dimensional chain-like coordination polymer and is further assembled by hydrogen-bonding interactions to form a three-dimensional network.