An ab initio molecular orbital study of SiHz + F2+ SiH2F2
نویسندگان
چکیده
The insertion of SiHs into Fz has been studied with MP2, CCD, CISD and QCISD. For fluorine approaching syn to the silicon lone pair, the complex is 2.5 kcal/mol below reactants and the insertion barrier is 0.5 kcal/mol above reactants at QCISD/63 1 G*; for the anti approach, there is no barrier (only a broad plateau) and insertion proceeds with inversion at silicon. With RQCISD, both pathways go directly to SiH2F2, but with RMP2 and RCCD, there are several structures in the SiH2F-F region of the surface that are artifacts of the level of theory.
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