A dinuclear copper(II) complex, [Cu-2(bhsNO(2))(2)(H2O)(2)] was isolated by
reacting Cu(O2CCH3)(2). H2O and 2-hydroxy-5-nitrobenzaldehyde benzoylhydra
zone (H(2)bhsNO(2)) in methanol, The X-ray structure of the complex has bee
n determined. The dinegative ligands bind the Cu(II) ions through the depro
tonated amide-O, imine-N and phenolate-O atoms. The pair of Cu(II) ions are
linked by the two phenolate-O atoms. The coordination geometry around each
Cu(II) is square pyramidal. The imine-N, amide-O and the bridging phenolat
e-O atoms form the square plane and the oxygen atom of a water molecule occ
upies the axial coordination site. The complex is redox active. Variable te
mperature (25-300 K) magnetic susceptibility measurements in the solid stat
e are consistent with an antiferromagnetic interaction between the two meta
l centres. The coupling constant J is found to be -186(5) cm(-1) by least-s
quares fitting of the magnetic susceptibility data using an expression deri
ved from the isotropic spin Hamiltonian, H = -2JS(1). S-2 (S-1 = S-2 = 1/2)
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