Crystal structure and magnetic properties of Cu(II) dinuclear complex with equatorial-axial bridging thiocyanate ligand: Showing ferromagnetic coupling.

[Display omitted] • The structure is binuclear unit of Cu linked through two thiocyanate. • The coordination geometry encompassing each of metal is a square pyramidal. • The 1D and 2D chain of Cu dinuclear unit is extended by Hydrogen bonds. • The magnetic susceptibility data show ferromagnetic coupling. A new Cu (II)-dinuclear, [Cu 2 -(µ-NCS) 2 (NCS) 2 (Nicotinamide) 4 ] complex was synthesized, and its single crystal X-ray structure was determined. The complex was further characterized by IR spectra, TGA and EPR spectroscopy and its magnetic behaviour was studied in detail. The complex consists of a binuclear unit in which two copper atoms are connected through two thiocyanate end to end (equatorial N-axial S) bridges. The coordination geometry around each of the metal centre in the dinuclear is square pyramidal, where basal plane is occupied by two nitrogen atoms from two nicotinamide moieties (Pyridine ring-N), one nitrogen atom from bridging thiocyanate and one nitrogen of non-bridging thiocyanate anion. The axial positions in the square pyramid of each copper centre of the dinuclear is occupied by sulphur atom of the two bridging thiocyanate moieties which are equatorially bonded to neighbouring copper atom of same dinuclear unit through nitrogen end. The dinuclear chain is extended by hydrogen bonding resulting into a 1D and 2D structure. The temperature dependent magnetic susceptibility of compound was carried out at 1000 Oe in the temperature range of 2–300 K. This behaviour indicates that the intra dinuclear magnetic interactions between the paramagnetic Cu(II) atoms is of ferromagnetic nature. [ABSTRACT FROM AUTHOR]