Evidence for the presence of dual emission in a ruthenium(II) polypyridyl mixed ligand complex

Abstract

The complex [Ru(bpy)₂(pztr)]⁺ 1 [bpy = 2,2′-bipyridyl, Hpztr = 3-(pyrazin-2-yl)-1,2,4-triazole] exhibits two emission maxima in fluid solution [ethanol–methanol (4:1)] over the temperature range 120–260 K; from fluorometric studies two well resolved emission maxima are observed at 590 and 700 nm, accompanied by two different lifetimes; the observations suggest the presence of two emitting states in this compound, one bpy and one pyrazine based.