Electronic spectra and crystal structure of dinuclear Cu(II) ‘paddle wheel’ acetate complex containing axially coordinated 3-methyl-4-nitropyridine-N-oxide

This article presents the electronic spectral characteristics enhanced with the structural, IR and magnetic data of the copper(II) acetate complex with 3-methyl-4-nitropyridine- N -oxide. The complex of the formula, [Cu 2 (OAc) 4 (3-mnpn) 2 ], belongs to the group of the ‘paddle wheel’ type species with a very short (2.58 Å) metal–metal distance. In the electronic spectra, new bands were found at 16,000 and 24,000 cm −1 , which have been tentatively assigned to the metal–metal interactions and solid state effects, respectively. The complex show fast kinetic exchange of the apical ligand, i.e. 3-methyl-4-nitropyridine- N -oxide.