C. Reichardt et al., SOLUTE SOLVENT INTERACTIONS AND THEIR EMPIRICAL DETERMINATION BY MEANS OF SOLVATOCHROMIC DYES, Pure and applied chemistry, 65(12), 1993, pp. 2593-2601
The solvatochromism, thermochromism, piezochromism, halochromism, and
potential chiro-solvatochromism of solutions of various pyridinium N-p
henoxide betaine dyes have been used by us and others to study UV/Vis-
spectroscopically the dye/solvent interactions in organic solvents of
different polarity, different temperature, different external pressure
, different electrolyte concentration, and different chirality.