Insertion Reactions of Monovalent Silicon: A Nonvanishing Barrier for the Silylidyne plus Hydrogen Reaction SiH + H2
نویسندگان
چکیده
Ab initio quantum mechanical methods have been applied to the SiH (X zrr) insertion into the Hz molecule. The transition state has no elements of symmetry. The classical barrier height is predicted to be 5.6 :I: I kcaljmol. The barrier is qualitatively consistent with an estimate from Jasinski's experimental reaction rates, which are much slower than those observed for the related CH + Hz, SiH + SiH4, and SiH2 + Hz reactions.
منابع مشابه
Combined Experimental and Theoretical Study on the Formation of the Elusive 2-Methyl-1-silacycloprop-2-enylidene Molecule under Single Collision Conditions via Reactions of the Silylidyne Radical (SiH; X<sup>2</sup>Π) with Allene (H<sub>2</sub>CCCH<sub>2</sub>; X<sup>1</sup>A<sub>1</sub>) and D4-Allene (D<sub>2</sub>CCCD<sub>2</sub>; X<sup>1</sup>A<sub>1</sub>)
The crossed molecular beam reactions of the ground-state silylidyne radical (SiH; XΠ) with allene (H2CCCH2; XA1) and D4-allene (D2CCCD2; X A1) were carried out at collision energies of 30 kJ mol−1. Electronic structure calculations propose that the reaction of silylidyne with allene has no entrance barrier and is initiated by silylidyne addition to the π electron density of allene either to one...
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