Macrocyclic complexes dinuclear copper sites

Magnetic susceptibility measurements carried out on (15) in the temperature range 5 to 300 K are consistent with a system composed of an antiferromagnetically coupled copper(II) pair and a magnetically independent third copper(II) ion. The macrocyclic complex therefore reproduces qualitatively features of the oxidase active site and the observed 2J value of -192 cm indicates the presence of a moderate antiferromagnetic interaction within the dinuclear moiety, albeit weaker than that of the protein type-3 site which is diamagnetic even at room temperature. 

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