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Two new complexes, {[MnAu 2 (CN) 4 (NITpPy) 2 (H 2 O) 2 ]} n ( 1 ) and {[Co(N(CN) 2 ) 2 (NITpPy) 2 (H 2 O) 2 ]} n ( 2 ), have been synthesized and characterized. The single-crystal X-ray analysis for the complexes 1 and 2 demonstrates that each M(II) (M = Mn or Co) ion assumes a distorted octahedral MN 4 O 2 coordination polyhedron. Four nitrogen atoms come from the cyanide groups and the pyridyl rings in a common plane, and two oxygen atoms come from the H 2 O molecules in trans -positions. The structures of complexes 1 and 2 illustrate that aurophilicity and/or hydrogen bonding interactions play important roles in increasing dimensionality. Magnetic investigations on complexes 1 and 2 show the presence of weak antiferromagnetic interactions.

Two novel 1D complexes, [Ni(hto){Au(CN)2}2][Ni(hto)](ClO4)2 · 4H2O (hto = 1,3,6,9,11,14-hexaazatricyclo[12.2.1.16,9]octadecane, in Scheme 1.) (1) and [Co(dien)2][{Au(CN)2}3] · 2H2O (dien = diethylenetriamine) (2) have been synthesized and characterized. The crystal structure of 1 confirmed the presence of nickel (II) chains via Au–Au interactions. The coordination geometry around the six-coordinate nickel (II) ion is slightly distorted octahedral with four nitrogen atoms of the macrocycle and two nitrogen atoms of the cyanides. The presence of Au–Au interactions have effectively increased the zero dimensional coordination polymer to a one dimensional system. In the complex 2, there are one cation, three anions, and two water molecules in the asymmetric unit. These components are interconnected through a combination of aurophilic attractions and hydrogen bonds and formed 1D chains.

A cyano-bridged nickel(II) compound, {[Ni(hto)][Ni(CN) 4 ]·( i -C 3 H 7 OH)·2H 2 O} n (hto=1,3,6,9,11,14-hexaazatricyclo[12.2.1.1 6,9 ]octadecane, in Scheme 1), has been prepared and characterized. Single crystal X-ray analysis reveals that the compound assumes a one-dimensional structure in which one nickel(II) ion is coordinated by four cyanide ligands and the other is coordinated by four nitrogen atoms of the macrocyclic ligand and two nitrogen atoms of the bridging cyanide ligands. The six-coordinate nickel(II) centres display an axially elongated octahedron, whereas the four-coordinate nickel(II) centres assume planar geometry. The polar guest isopropanol and water molecules are accommodated among [–Ni(hto)–NC–Ni(CN) 2 –CN–] n chains. The interguest and host–guest hydrogen-bonds formation link the chains and stabilize the whole crystal structure.