Fluorescence depolarization from 2,5,8,11-tetra-t-butylperylene globally analyzed upon excitation in S-1 and S-n

Abstract

The rotational dynamics of perylene and tetra-tertiary butylperylene are investigated by means of time-resolved fluorescence anisotropy experiments. In the global analysis of the polarised fluorescence decay traces, the preexponential factors in the anisotropy decay are linked over a series of n-alcohols while the rotational correlation times are linked over two excitation wavelengths. This approach allows for a high model discrimination power. The anisotropy decay of perylene could be analysed using a biexponential decay law with a fast in-plane and a slower out-of-plane rotation. By substituting perylene symmetrically by four tertiary butyl groups the two rotational correlation times become equal, resulting in a monoexponential anisotropy decay.