Photoelectron spectra and molecular properties. 15, The effects of α- and β-silyl substituents on π-systems

The photoelectron spectra of substituted ethylenes, H 2 C=CHX (X = H, CH 3, SiH 3, CH 2CH 3, CH 2SiH 3) are discussed in the light of results of CNDO-type molecular orbital calculations. The characteristic shifts of the first bands are explained in terms of a qualitative model for the substituent effects of α- and β-silyl groups upon π-systems