Generation of ionic species by photolysis of polysilylenes in dilute solution

Abstract

From flash photolysis studies (at λinc = 266 and 347 nm) involving the electrical conductivity and the optical absorption detection method it is inferred that poly(methylphenyl silylene), PMPSi, and poly(biphenylmethyl silylene), PBMSi, form ionic species in a monophotonic process in dilute tetrahydrofuran and dichloromethane solution at 295 K (ϕ(ion) ≈ 4×10−2, PBMSI and 1×10−2, PMPSi, in THF at λinc = 266 nm). The ionic species possess optical absorption bands between 350 and 500 nm with a maximum at about 380 nm. Both the photocurrent and the optical density at 380 nm decay with identical rates by a second order process (k2 ≈ 3 × 1011 dm3 mol−1 s−1, PBMSi in THF at 295 K).