Cyano-bridged bimetallic complexes of copper(II) with tetracyanonickelate(II). Crystal structure of [Cu(dpt)Ni(CN) 4

Abstract

Five new complexes of composition [Cu(dpt)Ni(CN) 4] ( 1) (dpt=dipropylenetriamine), [Cu(dien)Ni(CN) 4]·2H 2O ( 2) (dien=diethylenetriamine), [Cu( N, N′-dimeen)Ni(CN) 4]·H 2O ( 3) ( N, N′-dimeen= N, N′-dimethylethylenediamine), [Cu( N, N-dimeen)Ni(CN) 4]·H 2O ( 4) ( N, N-dimeen= N, N-dimethylethylenediamine) and [Cu(trimeen)Ni(CN) 4] ( 5) (trimeen= N, N, N′-trimethylethylenediamine) have been obtained by the reactions of the mixture of Cu(ClO 4) 2·6H 2O, appropriate amine and K 2[Ni(CN) 4] in water and have been characterized by IR and UV–Vis spectroscopies and magnetic measurements. The crystal structure of [Cu(dpt)Ni(CN) 4] ( 1) has been determined by single-crystal X-ray analysis. The structure of 1 consists of a one-dimensional polymeric chain Cu(dpt)NCNi(CN) 2CNCu(dpt) in which the Cu(II) and Ni(II) atoms are linked by CN groups. The nickel atom is four coordinate with four cyanide-carbon atoms (two cyano groups are terminal and two cyano groups (in cis fashion) are bridged) in a square-planar arrangement and the copper atom is five coordinate with two cyanide-nitrogen and three dpt-nitrogen atoms, in a distorted square-pyramidal arrangement. The temperature dependence of magnetic susceptibility (2–300 K) was measured for compound 1. The magnetic investigation showed the presence of a very weak antiferromagnetic interaction ( J=−0.16 cm −1) between the copper atoms within each chain through the diamagnetic Ni(CN) 4 2− ions.