Search

Abstract: Dry silver sulfadiazine (AgSD) is not light sensitive but shows a greenish-blue r.t. photoluminescence at λ max =482nm which is suggested to originate from an IL triplet. In the presence of water AgSD undergoes a partial hydrolysis with the formation of free sulfadiazine (HSD) which has been previously shown to be photoreactive. Moreover, irradiation of an aqueous suspension of AgSD leads also to the photoreduction of Ag+ to elemental silver. This photolysis might explain the origin of argyria which can occur when AgSD in contact with human skin is exposed to sun light [Copyright &y& Elsevier]

With regard to its electronic structure, the cation Icoll2+ (coll = collidine or 2,4,6-trimethylpyridine) is viewed as a coordination compound of iodine(I) with a p4 electron configuration. The lowest-energy excited state of Icoll2+ is suggested to be a ππ* collidine intraligand (IL) triplet which appears in absorption (λmax=332 nm, ϵ=250) and emission (λmax=405 nm, φ=0.001, τ∼90 ns). Owing to the heavy-atom effect of iodine this phosphorescence occurs at r.t. The longest-wavelength pp absorption is apparently obscured by the intense spin-allowed IL band at λmax=268 nm. [Copyright &y& Elsevier]