Abstract
Synthesis, structures, and electronic properties of silicon polymers and oligomers having hypervalent silicon moieties, polar substituents, or transition metal moieties are reported. UV spectra of pentacoordinate silicon oligomers reveal that the introduction of pentacoordinate silicon moieties into oligosilanes leads to a drastic change of the σ SiSi→σ* SiSi excitation energies. 29Si-NMR spectra have proved that the conformation of pentacoordinate oligosilanes is tightly locked, indicating that free rotation about the SiSi single bonds is nearly completely inhibited by electrostatic interaction. UV–vis spectra of polysilanes substituted with (alkoxycarbonyl)methyl groups exhibit unusual spectral properties such as long-wavelength absorption above 400 nm, and temperature- or solvent-dependent change of the UV spectra. Effective electron delocalization in SiRuRuSiC 6H 4 polymers was demonstrated by the absorption spectra. Solvent-sensitive skeletal rearrangement of the SiRuRuSi moieties gives rise to a remarkable change of the optical properties of the polymers.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have