Author/Authors :
Bongiovanni، نويسنده , , G and Loi، نويسنده , , M.A and Mura، نويسنده , , A and Piaggi، نويسنده , , A and Luzzati، نويسنده , , S and Catellani، نويسنده , , M، نويسنده ,
Abstract :
The relaxation dynamics of soluble polyalkylthiophenes obtained by the random copolymerisation of 3,4-dibutylthiophene and 3-butylthiophene monomers is investigated. In these systems, the effective conjugation length, the optical gap and the non-radiative decay rate are controlled by varying the content of disubstituted monomers, the steric hindrance of which induces a twisting angle between thiophene rings. Several indications are reported in favour of spectral diffusion of the photoexcitations. Migration processes mainly occur within a few tens of picoseconds.
