Synthesis and study of a polysilole

Abstract The thermal polymerization of Ph 2 Si(C≡CH) 2 reported in 1968 by Luneva et al. has been reexamined and spectroscopic analysis reveals that it does not produce the claimed structure. Different synthetic procedures yeild either a deep red polymer of molecular weight (MW ∼ 55,100 or a violet polymer of MW ∼ 105,300. Structural models and spectral examination of both systems strongly suggest that they are a polysilole of the form: If this structure is correct, this is the first example of a polymetallole with the heteroatom devoid of lone-pair electrons. The red polymer remains insulating even after doping with AsF 5 or I 2 . The conductivity of the intially semiconducting violet polymer ( σ ∼ 10 −7 S/cm), however, increases by four orders of magnitude upon doping with I 2 . Photoabsorption, photoluminescence, and ESR measurements are also described and discussed. The results suggest that this polysilole is intrinsically an insulator.