Excited state dynamics of phenylene ethynylene and phenylene vinylene oligomer films studied with femtosecond spectroscopy

Summary form only given. We study the time resolved spectroscopy of oligomers of phenylene ethynylene (OPE) and phenylene vinylene (OPV) using femtosecond pulses. They both display large fluorescent emissions, similar to their corresponding polymers, and they can be grown as thin films with an important degree of orientation. We performed pump-probe experiments using a Ti:sapphire laser amplified at 5 kHz. Part of the beam is doubled in a BBO crystal to generate 150 fs pump pulses at 400 nm, another part is used to generate a dispersion compensated spectral continuum. The differential transmission /spl Delta/T/T(/spl lambda/, /spl tau/) is measured as a function of the probe wavelength /spl lambda/ and pump-probe delays /spl tau/ with an OMA detector or a synchronous detection.