Ab initio study of isomerization reaction from c-OSiH2O to t-OSiHOH

The isomerization reaction from c-OSiH2O to t-OSiHOH, a vital reaction to u nderstand the spontaneous ignition of silane, has been reinvestigated with Gaussian-2 theory and the CASSCF(6,6) method. It has been found that the re action proceeds through two consecutive steps; i.e., c-OSiH2O undergoes iso merization to yield w-OSiH2O, and then the latter is converted to t-OSiHOH. The G-2 energy of the transition state of the latter process is 4.3 kcal/m ol higher than that of the former. However, the G-2 energy of this higher t ransition state plus H atom is still 4.8 kcal/mol lower than that of the or iginal reactants of SiH3 + O-2 (C) 1999 Elsevier Science B.V. All rights re served.