Photoinduced absorption measurements of triplet states in poly(p-pyridine)

We report cw photoinduced absorption (PIA) measurements of poly(p-pyridine) (PPY). Three correlated, induced features are found below the pi-->pi(*) t ransition. All have a strong temperature dependence and similar lifetimes o f ca 10 ms. Comparing to ZINDO/S-CI calculations of the triplet manifold we find good agreement and so conclude that the PIA represents transitions wi thin the triplet manifold. However, as yet we have not been able to definit ively measure a v(-1) chop rate dependence for the PIA signals indicative o f monomolecular recombination.