In search of the thermo/halochromism of the E(T)(30) pyridinium-N-phenolate betaine dye

Abstract

The thermohalochromic behavior of Reichardt's E(T)(30) betaine - the temperature-dependent variation of its halochromic band in the presence of a cation - was investigated for the first time in NaI solutions of HBD- (methanol, ethanol, 1-propanol, 1-butanol) and non-HBD-solvents (acetonitrile, dimethylformamide) at 15 and 55 °C. The solvent-dependent thermohalochromism of the pyridinium-N-phenolate betaine dye was interpreted in terms of the effect of the temperature on the dye-cation association in solution.