Germanium-silicon copolymers

The copolymer (Me2SiPh2GeMe2Si) (7) had a molecular weight of Mw = 1.1 x 103 (Mw/Mn = 1.31) and was isolated in 25% yield. The authors claim that the polymerizabil-ity of a,electrochemical conditions is mainly affected by the substituents at the chlorinated terminal silicon atoms, which provides interesting options for the design of copolymers with ordered sequences of silicon and germanium atoms. 

An example of a one-dimensional superlattice structure is structure 1, which is an ordered copolymer. The skeleton is formed by silicon and germanium atoms. A unit cell is three times larger than that of a homopolymer. The band structure of this ordered copolymer changes to the zone-folded profile, which may result in a characteristic absorption spectrum. 

The matrix array detector (128 x 128) associates P(VF2-VF3) copolymer with a silicon CCD matrix. This detector made by Thomson-CSF/LCR and TCS has been characterized al room temperature using an IR germanium optics. The following table summarizes the performances of this detector. 

High-molecular-weight germanium-silicon copolymers have been prepared by the sodium assisted cocondensation of R2GeCl2 and R2SiCl2 [11] (see Eq. 8.3). 

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