Exciton dynamics in soluble poly(p-phenylene vinylene)

We report studies of poly(2,5-dioctyloxy paraphenylene vinylene) thin films and solutions by a variety of transient, steady state, and nonlinear optical techniques. The energy states and optical absorption of the dominant even and odd parity excitons have been determined. Photogenerated singlet excitons are characterized by strong stimulated emission and two photoinduced absorption bands. Triplet excitons are found to have a single absorption band; intersystem crossing time from the singlet to the triplet manifolds is estimated to be ~4 ns in films and ~20 ns in solutions.