Synthesis, crystal structure and magnetic properties of a new ferromagnetic nickel(II) dimer derived from a hexadentate Schiff base ligand

• Published in: Polyhedron Vol. 22; no. 2; pp. 257 - 262
• Main Authors: Deoghoria, Soma, Sain, Sushama, Soler, Monica, Wong, W.T, Christou, George, Bera, Sujit K, Chandra, Swapan K
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 15.01.2003; Elsevier
• Subjects: Binuclear nickel(II) complex; Chemistry; Chemistry, Inorganic & Nuclear; Crystal structure; Crystallography; End-on azido ligand complex; Hexadentate ligand; Magnetic properties; Physical Sciences; Science & Technology; Terminal azido ion complex; Hexadentate ligand; Binuclear nickel(II) complex; Terminal azido ion complex; Crystal structure; Magnetic properties; End-on azido ligand complex; TRANSITION-METAL COMPLEXES; GROUND-STATE; hexadentate ligand; POLYNUCLEAR COMPLEXES; COPPER(II) COMPLEXES; end-on azido ligand complex; DI-MU-AZIDO; BINUCLEAR COMPLEXES; magnetic properties; MAGNETOSTRUCTURAL CORRELATIONS; terminal azido ion complex; crystal structure; END-ON AZIDO; DINUCLEAR COMPLEXES; COUPLED DIMER; binuclear nickel(II) complex
• ISSN: 0277-5387
• DOI: 10.1016/S0277-5387(02)01336-0

A new end-on bis(μ-azido) nickel(II) complex of the formula [Ni 2(L 1)(N 3) 4] ( 1) (L 1=hexadentate Schiff base ligand made from the reaction of 2 moles of 2-benzoyl pyridine and 1 mole of triethylenetetramine) has been prepared and characterized by single crystal X-ray diffraction studies. Each nickel center is coordinated in a distorted octahedral (NiN 6) fashion consisting of three nitrogen atoms from the hexadentate ligand moiety, two nitrogen atoms from two end-on azido ligands and the last one from another terminal azido ion. The variable temperature magnetic susceptibility of compound 1 shows that the nickel centers are ferromagnetically coupled. The NiNNi bridge angles are very similar [98.36(8)° and 97.66(9)°] and the Ni⋯Ni separation is 3.155(1) Å. The magnetic exchange coupling constant J=21.8 cm −1 is consistent with the structure and the value has been compared with some similar reported compounds. A new end-on (μ 1,1-N 3) nickel(II) binuclear complex has been synthesized from a hexadentate Schiff base ligand and characterized by X-ray crystallographic analysis. Each nickel atom is in a distorted octahedral coordination with two end-on azido ligands and a terminal azido ion. The nickel centers are ferromagnetically ( J=21.8 cm −1) coupled and the magnetic exchange value is consistent with the NiNNi bridge angle as well as the Ni⋯Ni separation (3.155(1) Å).