We report the evaporation of astable cyclic silylene and its oxidation (with ozone or N 2 O) through oxygen atom transfer to form the corresponding silanone under matrix isolation conditions.Asuncomplexed silanones are rare owing to their very high reactivity,this method provides an alternative route to these sought-after molecules.T he silanone,a sw ell as an ovel bicyclic silane with ab ridgehead silicon atom derived from an intramolecular silylene CÀHb ond insertion, were characterized by comparison of high-resolution infrared spectra with density functional theory (DFT) computations at the M06-2X/cc-pVDZ level of theory.