Polysilanes coupling constants

The proton NMR spectral data of organopolysilanes have often been published incidental to preparative studies (51, 54, 62, 74, 108, 119, 177, 187, 190). Only recently has a systematic investigation to determine the chemical shifts and coupling constants in linear and cyclic permethylated polysilanes, and to study the effects of substituents on the NMR properties of methyl derivatives of disilane and trisilane been reported (see Table V-VII) (206). 

C and 29Si coupling constants, i.e., /(Si—CH3), /(Si—Si—CH3) and /(13C—H), in some of the polysilanes are listed in Table VII. /(Si—CH3) decreases slightly with increasing catenation in the same way as found for analogous polymethyltin compounds, but differences are quite small for the polysilanes. 

---