Femtosecond Excited-State Dynamics of Polydiacetylene

摘要

Polydiacetylenes are prototypical conjugated polymers exhibiting exceptionaloptical and electronic properties. Unlike most conjugated polymers, polydiacetylenes can be synthesized in optical-quality thin films, which makes them suitable for optical and nonlinear optical studies. In particular, Langmuir-Blodgett techniques have produced ultrathin films of polydiacetylene 15-8, referred to as PDA 15-8. Also, solution shear growth methods have produced thin films of single-crystal polydiacetylene p-toluene sulfonate, referred to as PTS. The single-crystal polydiacetylenes are particularly interesting because they exhibit quasi-one-dimensional behavior, which includes enhanced nonlinear properties. Previous experiments in different forms of polydiacetylene have examined the excited-state dynamics. The excited-state lifetime has been measured by various researchers to be 1-2 ps. (jes)