Dimer formation of a stilbenesulphonic acid salt in aqueous solution

✍ Scribed by Jan Alsins; Mikael Björling; István Furó; Valdis Egle

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 72 KB
• Volume: 12
• Category: Article
• ISSN: 0894-3230
• DOI: 10.1002/(sici)1099-1395(199903)12:3<171::aid-poc104>3.0.co;2-7

✦ Synopsis

The steady-state and time-resolved fluorescence and 1 H NMR spectra of a stilbenesulphonic acid salt, commonly used as an optical brightening agent, was studied as a function of concentration in aqueous solution. The aggregates, formed at higher concentrations, were shown to be predominantly dimers with the central stilbene moieties of the molecules stacked plane-parallel. The equilibrium constant for the dimer formation at 25 °C was obtained from both NMR and fluorescence measurements.