Microwave photoconductivity and polaron formation in poly[methyl(phenyl)silylene]

The photogeneration of charge carriers in poly[methyl(phenyl)silylene] (PMPSi) is a multistage process including, photoinduced electron transfer and relaxation of the charge-transfer state which results in ion (polaron) pair formation. The radical ions are usually detected by transient optical absorption. Covalently linked molecular dipoles or Coulomb-correlated ion-pairs, and free and shallow localized carriers can also be detected by the method of time-resolved microwave conductivity (TRMC). This method is based on the proportionality of the relative change in the reflected microwave power and the "induced conductivity" due to dipolar transitions that are caused by the absorption of a light. The formation of radical ion-pairs in poly[methyl(phenyl)silylene] upon light excitation was studied by the abovementioned techniques. (C) 2000 Elsevier Science S.A. All rights reserved.