Nickel(II)dicyanamide complexes containing a diamine as end-capping ligand: Composition tailored architectures and magnetic properties

Abstract

One mono- and two polynuclear nickel(II)dicyanamide complexes containing 1,3-propanediamine as an end-capping ligand have been synthesized through systematic variation of molar ratios the building components, and characterized structurally and magneto-structurally. One 0D monomer trans- [Ni(pn) 2 (dca) 2 ] ( 1 ), one neutral 2D polymer [Ni(pn)(dca) 2 ] n ( 2 ) and one polycationic 1D polymer [Ni(pn) 2 (dca)] n (PF 6 ) n ( 3 ) (pn = 1,3-propanediamine; dca = dicyanamide) have been synthesized and X-ray crystallographically characterized. 1 has terminal trans- Ni(dca) 2 unit, 2 contains both double bridged Ni–(NCNCN) 2 –Ni and single bridged Ni–(NCNCN)–Ni units in alternate fashion and 3 consists of single Ni–(NCNCN)–Ni bridge by covalent bonds. The nickel(II) centers are six-coordinated with distorted octahedral geometry. Multiple lateral N–H···N, C–H···N, N–H···F and C–H···F hydrogen bondings promote dimensionality. Variable-temperature magnetic measurements indicate weak antiferromagnetic interactions through μ 1,5 bridge(s).