Specific Versus Nonspecific Solvent Effects on the Intramolecular Charge Transfer in Aminonapthalene Derivatives

Abstract

Solvent effect on the fluorescence emission absorption and spectra of 2-naphthylamine-6-sulfonate (2NA6S) and 1-naphthylamine-4-sulfonate (1NA4S) were investigated. Excited-state lifetime measurements were also measured in a variety of solvents. The spectral shifts are well correlated with several multiparametric relationships that predict the participation of hydrogen bonding interactions (specific) versus non-hydrogen bonding interactions (non-specific) on the photophysical properties. Kamlet-Taft with their three parametric relationships which were then improved by Catalán by splitting the * (dipolarity/polarizability) to parameters namely, solvent’s polarizability) solvent’s dipolarity, and very recently Laurence relationships. Kamlet-Taft relationship has shown that the absorption energy is mainly regulated by specific interactions while the emission energy is monitored by the non-specific interactions. On the other hand, Catalán’s dealing has shown that