Dinuclear Complexes of MII Thiocyanate (M = Ni and Cu) Containing a Tridentate Schiff-Base Ligand: Synthesis, Structural Diversity and Magnetic Properties

✍ Scribed by Suparna Banerjee; Michael G. B. Drew; Can-Zhong Lu; Javier Tercero; Carmen Diaz; Ashutosh Ghosh

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 149 KB
• Volume: 2005
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200500080

✦ Synopsis

Abstract

A dinuclear Ni^II^ complex, [Ni~2~(L)~2~(H~2~O)(NCS)~2~]·3H~2~O (1) in which the metal atoms are bridged by one water molecule and two μ~2~‐phenolate ions, and a thiocyanato‐bridged dimeric Cu^II^ complex, [Cu(L)NCS]~2~ (2) [L = tridentate Schiff‐base ligand, N‐(3‐aminopropyl)salicylaldimine, derived from 1:1 condensation of salicylaldehyde and 1,3‐diaminopropane], have been synthesized and characterized by IR and UV/Vis spectroscopy, cyclic voltammetry and single‐crystal X‐ray diffraction studies. The structure of 1 consists of dinuclear units with crystallographic C~2~ symmetry in which each Ni^II^ atom is in a distorted octahedral environment. The Ni–O distance and the Ni–O–Ni angle, through the bridged water molecule, are 2.240(11) Å and 82.5(5)°, respectively. The structure of 2 consists of dinuclear units bridged asymmetrically by di‐μ~1,3~‐NCS ions; each Cu^II^ ion is in a square‐pyramidal environment with τ = 0.25. Variable‐temperature magnetic susceptibility studies indicate the presence of dominant ferromagnetic exchange coupling in complex 1 with J = 3.1 cm^–1^, whereas complex 2 exhibits weak antiferromagnetic coupling between the Cu^II^ centers with J = –1.7 cm^–1^. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)