Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 4 of 4
Full-Text Articles in Inorganic Chemistry
Nature Of The Si-N Bond In Silatranes, Mark S. Gordon, Marshall T. Carroll, Jan H. Jensen, Larry P. Davis, Larry W. Burggraf, R. Martin Guidry
Nature Of The Si-N Bond In Silatranes, Mark S. Gordon, Marshall T. Carroll, Jan H. Jensen, Larry P. Davis, Larry W. Burggraf, R. Martin Guidry
Mark S. Gordon
Both ab initio and semiempirical calculations are used to investigate the structure and bonding in substituted silatranes. In agreement with gas-phase experiments, which fmd Si-N distances that are 0.25-0.35 A longer than those in the crystal phase, the Si-N distance (for example, in methylsilatrane) is predicted to be much larger than that observed in the crystal. Nonetheless, a bond critical point is found between Si and N, suggesting the existence of an Si-N bond in these compounds. It is found that the energy cost for constraining the Si-N distance in hydroxysilatrane to a value similar to that observed in the …
A New Twist On Pseudorotation, Theresa L. Windus, Mark S. Gordon, Larry W. Burggraf, Larry P. Davis
A New Twist On Pseudorotation, Theresa L. Windus, Mark S. Gordon, Larry W. Burggraf, Larry P. Davis
Mark S. Gordon
For pentacoordinated structures in a trigonal bipyramidal ar· rangement, Berry1 proposed a "pseudorotation" mechanism whereby two such isomers can interconvert through a tetragonal transition state (TS). This Berry pseudorotation mechanism was demonstrated explicitly for SiH5- by following the MP22/6· 31G(d)3 minimum energy path4 (MEP).
Gas-Phase And Computational Studies Of Pentacoordinate Silicon, Robert Damrauer, Larry W. Burggraf, Larry P. Davis, Mark S. Gordon
Gas-Phase And Computational Studies Of Pentacoordinate Silicon, Robert Damrauer, Larry W. Burggraf, Larry P. Davis, Mark S. Gordon
Mark S. Gordon
We have demonstrated that a wide variety of pentacoordinate silicon anions (siliconates) should be stable and can be prepared by combining the predictive powers of MNDO and ab initio computational methods and the flowing afterglow (FA) experimental technique. MNDO has been used to compute the anion affinities of 91 siliconates; all but five of these are predicted to be stable with respect to the loss of an anion. Twenty-four siliconates, most of them previously unreported, have been prepared and studied in the FA. The MNDO predictions were, in general, consistent with the experimental results and with trends previously reported by …
Thermal Decomposition Of Silane, Mark S. Gordon, David R. Gano, J. Stephen Binkley, Michael J. Frisch
Thermal Decomposition Of Silane, Mark S. Gordon, David R. Gano, J. Stephen Binkley, Michael J. Frisch
Mark S. Gordon
The essential features of the potential energy surface for the thermal decomposition of silane have been calculated with extended basis sets, augmented by correlation corrections. It is predicted that the transition state for the molecular elimination lies 56.9 kcaljmol above silane. For the reverse reaction, the transition state is less than 2 kcal/mol above the separated fragments, silylene and molecular hydrogen, but 4.8 kcal/mol above a long-range potential well. In the latter, the silylene-H2 separation is 1.78 A, and the bond in H2 has stretched by more than 0.05 A. This indicates a significant electronic interaction between the fragments even …