Copper(II)-Nickel(II) Induced Cyanide Bridged 2D Heterometallic Coordination Polymer: Synthesis, X-ray Structure and Magnetic Study

Abstract

One new two-dimensional heterometallic coordination polymer [Cu3Ni(L)2(CN)6]n (1) [L = 2-methylethylenediamine, CN– = cyanide ion] was synthesized and characterized by X-ray crystallography. Compound 1 crystallizes in the monoclinic C2/c space group. The single crystal X-ray structure of compound 1 indicated that it is a 2D coordination polymer with three copper(II) ion embedded with [Ni(CN)4]2- molecular ion in architecture through μ-CN/μ-NC bridges results heterometallic polymer. In compound 1, each Cu1 center with a CuN5 chromophore is encompassed by four N atoms of the two different bidentate amine (L) and one N atom of μ-NC ion, while both Cu2 and Cu3 centres are connected by three N atoms of μ-NC ions having CuN3 chromosphere and Ni1 are coordinated by three μ-CN and one terminal CN ions with NiC4 chromophore. Three copper centers and one nickel center are interlinked through μ-CN/μ-NC forming {-Cu1(L)2(μ-NC)Ni1(CN)(μ-CN)2Cu2(μ- NC)Cu3(μ-NC)-} unit to fabricate a 2D hetero metallic polymer. In the crystalline state of compound 1, each 2D polymer is further propagated through intermolecular N-H···N hydrogen bonds corroborant a supramolecular 2D network structure. Variable temperature magnetic susceptibility study displayed a weak antiferromagnetic spin coupling presumably due to the diamagnetic tetracyanonickellate bridging among the CuII ions.