A spectroscopic study of the optical properties of a nitrobenzoxadiazole derivative in solution : the role of specific interactions

The role of specific interactions on the optical properties of organic dyes is an important issue when designing optimized organic chromophores to be used in optoelectronic applications. The role of quantum chemical modeling of environmental effects can be of relevance in this respect but it is a very delicate issue to be tackled with different approaches. In this Letter we show that a simple dimer approach (one solvent + one solute molecule) is enough to reproduce the correct solvatochromic behavior of 4-hexylamino-7-nitro-2,1,3- benzoxadiazoles, which belongs to a class of molecules well known for their fluorogenic properties.