Effect of proton-donor solvent and structural flexibility of prodan and laurdan molecules on their spectral-luminescent properties

The influence of structural flexibility on dipole moments, energy-level locations, and charge distributions in prodan and laurdan molecules was studied. A quantum-chemical calculation of isolated prodan and laurdan molecules in the fluorescent state geometry was conducted. Rate constants for radiative and non-radiative processes and fluorescence quantum yields for these probe molecules were calculated. Interaction centers of prodan and laurdan with a proton-donor solvent were estimated quantitatively. The possibility of using fluorescent probes for estimating the polarity of proton-donor and proton-acceptor solvents was shown. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 3, pp. 334–341, May–June, 2009.