Solution stability of ethylimidazolate bridged homobinuclear (CuII-CuII) and heterobinuclear (CuII-ZnII) complexes: The pH-dependent stability of an aqueous solution of solid complexes by spectrometry

The pH-dependent stability of an aqueous solution of ethylimidazolate bridged homobinuclear [(Phen)2Cu-μ-Et-im-Cu(Phen)2](BF4)3 and a heterobinuclear [(Phen)2Cu-μ-Et-im-Zn(Phen)2](BF4)3 complex (μ-Et-im = 2-ethylimidazolate ion) have been studied by X-band electron spin resonance and UV-visible spectroscopy. These two complexes have been synthesized and characterized. The spectroscopic data of these complexes have been described as possible models for superoxide dismutase (SOD). Magnetic moment and e.s.r. spectral measurements of the homobinuclear complex have shown an antiferromagnetic exchange interaction. From pH-dependent e.s.r. and UV-visible spectral measurement studies, these complexes have been found to be stable over 8.5 pH range.