Spectral and photophysical properties of trans-2-styrylanthracene rotamers, derived by kinetic fluorescence analysis. A comparison with the results obtained by statistical procedures

A kinetic (KFA) and a statistical (PCA-SM) method were applied to resolve the fluorescence spectra of the rotamer mixtures of trans-1-(2-anthryl)-2-(phenyl)ethylene (trans-2-styrylanthracene, 2-StAn) in two different non-polar solvents. The KFA method is based on the observation, at an isoemissive frequency, of the fluorescence quantum yield and decay kinetics of the rotamer mixtures as a function of the excitation wavelength. The statistical PCA-SM treatment is based on the self-modeling procedure guided by the Lawton and Sylvestre non-negativity constraint (L.-S.). The results obtained by these two different methods are in very good agreement thus confirming the validity of L.-S. self-modeling constraint for this system. The spectral properties of the two rotamers are also compared with those derived from a different PCA-SM treatment in another laboratory.