Photophysical Primary Processes in Solutions of p‐Substituted Dialkylanilines

Abstract

Abstract The variation of the acceptor substituent in p‐substituted dimethylanilines leads to a reversal of the 1 L b and 1 L a type excited states. By fluorescence and fluorescence polarization measurements it is shown to occur between p‐dimethylaminobenzonitrile (DMABN) and p‐di‐methylaminoacetophenone. — As a consequence, the two components of dual fluorescence emitted by these molecules in polar solutions originate from different hypersurfaces in the first case but from the same in the second case. The fluorescence of p‐dimethylaminobenzoic acid ethyl ester in nonpolar solutions is assigned to arise from S 2 .