Coexisting intraligand fluorescence and phosphorescence of hafnium(IV) and thorium(IV) porphyrin complexes in solution

Abstract

The closed-shell metalloporphyrins Hf (TPP) (OAc)(2) and Th(TPP) (acac)(2) (TPP = dianion of tetraphenylporphyrin, OAc = acetate, acac = acetylacetonate) display intraligand fluorescence and additional heavy-atom-induced intraligand phosphorescence, which is observed at room temperature in fluid solution and very efficiently quenched by O-2 with potential significance for the sensing of trace amounts of dioxygen. (C) 2002 Elsevier Science B.V. All rights reserved.