Double Davydov's splitting of the visible absorption band of rhodamine B

Abstract

Experimental evidence of a double splitting in the visible absorption band of rhodamine B in aqueous solutions due to dimerization is reported. The shape and position of the split bands suggest that two separate electronic states are concerned. The first corresponds to the absorption band at 538 nm and the second to the shoulder at 556 nm in the monomer absorption spectrum. The structural implications of this assignment are discussed.