Association of Thymolsulfonephthalein and Cresolsulfonephthalein Anions with Cationic Cyanines in Aqueous Solution
The formation of associates between one- or two-charged anions of sulfonephthalein dyes – thymolsulfonephthalein, cresolsulfonephthalein – and cyanine cations (pinacyanol, quinaldine red) has been considered in aqueous solution. Equilibrium association constants have been determined using spectrophotometric data. By semiempirical methods the enthalpy of formation and the eventual structure of ions and associates have been established.