THE PHOTOLUMINESCENCE OF POLY(METHYLPHENYLSILYLENE) - THE ORIGIN OF THE LONG-WAVELENGTH BROAD-BAND

The photoluminescence of poly(methylphenylsilylene) consists of a relatively sharp band at 350 nm and a significantly broad band in the 400-500-nm region. The luminescence behavior is investigated at low temperatures in an effort to identify the origin of the long-wavelength broad emission. The excitation spectra differ for the sharp and the broad emission bands: The broad emission band is more enhanced when the excitation is carried out at the π,π* absorption band of the phenyl substituent as compared to the excitation at the σ,σ* absorption band of the silicon skeleton. The lifetimes are of the order of picoseconds for both the sharp and the broad bands.