New unsymmetrical polysilanes, -[R-1(Me)Si](n)-(1-3),-[R-2(Me)Si](n)-(4-6), and -[R-2(Ph)Si](n)-(7-9), bearing pendant sila-substituted alkyl groups of varying chain length [R-1:(CH2)(3)Si&3bond;; R-2: (CH2)(2)Si&3bond;] have been synthesized by Wurtz coupling reaction. These polysilanes reveal a monomodal molecular weight distribution with M-w in the range (237-31) x 10(3) for 1-6 and (2.9-2.3) x 10(3) for 7-9. Stereochemical configuration of polysilane 2 has been deduced from a detailed analysis of C-13{H-1} NMR resonances of backbone Si-Me groups and suggests a predominantly atactic microstructure. UV absorption spectra of polysilanes 1-3 (λ(max): 303-317 nm; ε: 2800-5900 (Si repeat unit)(-1) dm(3) cm(-1)) feature a discernible bathochromic shift and higher extinction coefficient values in comparison to those observed for analogous polysilanes 4-6 (λ(max): 296-305 nm; ε: 2000-3000 (Si repeat unit)(-1) dm(3) cm(-1)). These results coupled with photoluminescence (PL) spectra indicate that electronic properties of these polysilanes are influenced by the pendant sila-alkyl chain length as well as by steric effect of substituents on a silicon atom. UV and PL emission and excitation spectral characteristics of phenyl-substituted polysilanes 7-9 provide evidence in favor of (1)(σ-π*)(CT) charge-transfer phenomenon.