Picosecond excited states in poly(aryleneethynylene) s

Temporal and spectral excited-state absorption characterisation of polyaryleneethynylenes in solution has been performed using Kerr ellipsometry. The position of the 2Ag level has been determined for three different polymers of this family. Depending on the aromatic substituent, the 2Ag state is located approximately 1.4 to 1.7 eV above the optical bandgap, with a cross-section of 7 to 20 × 10−17 cm2 and the radiative decay times are found to be around 450 ps.