A comparison of the behaviour of photochemically produced species in Co(acac)3 benzene solutions with the behaviour of 60Co-recoil species in the similar systems

The effects of additives on the behaviour of the Co(acac)2 produced photochemically in Co(acac)3 benzene solut[ons were compared with those previously observed for the 60Co recoil species in Co(acac)3 benzene solutions. The reformation of Co(acac)3 from Co(acac)2 was found to be enhanced in the presence of less stable metal acetylacetonates, indicating a striking similarity to their effect on the reactions of the 60Co recoil species. The 4x10-2 solution of Co(acac)3 in benzene was exposed to a 500-W high pressure mercury lamp for several hours at an ambient temperature. After the Co(acac)3 benzene solutions containing various additives had been kept standing for a desired length of time at 30 or 50 deg C, they were extracted with three portions of 3% EDTA aqueous solution containing 0.8% sodium potassium tartarate. The amount of Co(acac)3 in the benzene solutions was determined spectrophotometrically at 595 mμ, the wavelength of the maximum in the visible absorption band. (N.L.Gy.)