Crystal structure, synthesis and thermal properties of bis(acetonitrile-κN)bis(4-benzoylpyridine-κN)bis(isothiocyanato-κN)nickel(II)

Abstract

In the crystal structure of the title compound, [Ni(NCS)2(CH3CN)2(C12H9NO)2] or Ni(NCS)2(4-benzoylpyridine)2(acetonitrile)2, the NiII ions are octahedrally coordinated by the N atoms of two thiocyanate anions, two 4-benzoylpyridine ligands and two acetonitrile molecules into discrete complexes that are located on centres of inversion. In the crystal, the discrete complexes are linked by centrosymmetric pairs of weak C—H...S hydrogen bonds into chains. Thermogravimetric measurements prove that, upon heating, the title complex loses the two acetonitrile ligands and transforms into a new crystalline modification of the chain compound [Ni(NCS)2(4-benzoylpyridine)2], which is different from that of the corresponding CoII, NiII and CdII coordination polymers reported in the literature. IR spectroscopic investigations indicate the presence of bridging thiocyanate anions but the powder pattern cannot be indexed and, therefore, this structure is unknown.