“Supersilyl” Compounds (R 3 Si) 3 SiSi(SiR 3 ) 3 and (R 3 Si) 3 SiC 6 H 4 Si(SiR 3 ) 3 : Structures and Properties

Remarkable properties characterize organosilicon compounds like 1 and 2: some of their structures are distorted by steric overcrowding and their first ionization energies drop as a result of additional radical cation stabilization to unexpectedly low values. In the π-radical anion of 2 considerable spin delocalization in the SiSi3 frameworks is detected by ESR/ENDOR spectroscopy.