RADIATION-INDUCED CHEMICAL-TRANSFORMATIONS OF HAFNIUM OCTA-4-TERT-BUTYLDIPHTHALOCYANINE IN ETHANOL

The continuous radiolysis of hafnium octa-4-tert-butyldiphthalocyanine (Pc2(t)Hf) in deaerated and aerated ethanol solutions was studied usi ng spectrophotometric and ESR detection techniques. It was found that the transformations of Pc2(t)Hf in the absence of oxygen are caused by its interaction with hydroxyethyl radicals and result in colorless di amagnetic products. More complicated processes occur in the presence o f air, and form at least three products: colored paramagnetic radical cations Pc2(t)Hf.+ produced via oxidation of Pc2(t)Hf by peroxide radi cals, colorless paramagnetic adducts, and a diamagnetic compound that displays absorption bands coinciding in the visible region with those of radical cations. Some time after irradiation, the parent Pc2(t)Hf c omplex is reformed both in deaerated and aerated ethanol solutions.