Synthesis, structure and luminescence behaviour of heptacoordinated one-dimensional coordination polymers of the type [Cd(L)(dca)] (X) (L = a pentadentate Schiff base; dca = dicyanamide; X =ClO4-, PF6-)

Stereochemical Geometries and Photoluminescence in Pseudo-Halido-Zinc(II) Complexes. Structural Comparison between the Corresponding Cadmium(II) Analogs

Six pseudohalide zinc(II) containing a variety of N-donor auxiliary amines were structurally characterized. These include two mononuclear trigonal bipyramidal [Zn(NTB)(N3)]ClO4·½H2O (3) and [Zn(TPA)(NCS)]ClO4 (4), two distorted octahedral [Zn(1,8-damnph)2(dca)2] (5) and [Zn(8-amq)2(dca)2] (6a) as well as two 1D polymeric chains catena-[Zn(isq)2(μ1,5-dca)2] (7) and catena-[Zn(N,N-Me2en)2(μ1,5-dca)]dca (8), where NTB = tris(2-benzimidazolylmethyl)amine, TPA = tris(2-pyridylmethyl)amine, 1,8-damnph = 1,8-diaminonaphthalene, 8-amq = 8-amino-quinoline, isq = isoquinoline (isq) and N,N-Me2en = N,N-dimethylethylenediamine. In general, with the exception of 6 and 8, the complexes exhibited luminescence emission in MeOH associated with red shift of the emission maxima, and the strongest visible fluorescence peak was detected at 421 nm (λex = 330 nm) in the case of Complex 5.

Coordination Polymers in Dicyanamido-Cadmium(II) with Diverse Network Dimensionalities

The synthesis and structural characterization of six dicyanamido-cadmium(II) complexes are reported: catena-[Cd(μ1,3-dca)(μ1,5-dca)(3-ampy)] (1), catena-[Cd3(μ1,3,5-dca)2(μ1,5-dca)4(pyNO)2(H2O)2] (2), catena-{Cd(H2O)2(μ1,5-dca)2](2,6-lut-NO)} (3), catena-[Cd(Me2en)(μ1,5-dca)2] (4), catena-[Cd(Me4en)(μ1,5-dca)2] (5), and [Cd(1,8-damnp)2(dca)2] (6), where dca = dicyanamide anion, 3-ampy = 3-aminopyridine, pyNO = pyridine-N-oxide, 2,6-lut-NO = 2,6-lutidine-N-oxide, Me2en = N,N-dimethyl-ethylenediamine, Me4en = N,N,N′,N′-tetramethyl-ethylenediamine, and 1,8-damnp = 1,8-diaminonaphthaline. The coordination polymers have different dimensionalities: 1 and 5 form 3D networks structures; 3 and 4 form polymeric 1D chains and 1DD double chains, respectively. Ribbons of three fused polymeric chains are observed in 2. In 6, the mononuclear complex units form a hydrogen-bonded supramolecular 3D network. In the coordination polymer compounds, the dca linkers display three bonding modes: the most common μ1,5-dca and the least popular μ1,3- and μ1,3,5-dca bonding. The luminescence emission and thermal properties of the complexes were investigated.