Atomistic view of the recombinative desorption of H2 from H/Si(100).

Calculation of desorption and migration of hydrogen on SiGe(100)-2×1 surface using density functional theory

Ab initio calculations have been carried out to investigate the H-atom migration and H2 desorption on the mixed SiGe(100)-2×1 surface using the Si9-xGexH13, Si14GeH19 and Si13Ge2H19 cluster models. The H2 recombinative desorption is the rate-determining step in hydrogen migration and desorption on SiGe(100) surface since the energy barrier of H-atom migration is generally lower than that of H2 ...

A dynamically and kinetically consistent mechanism for H2 adsorption/desorption from Si(100)-2 x 1.

Curiously, H2 desorption from Si~100!-231 follows approximately first-order kinetics rather than the expected second-order kinetics, arousing interest about the mechanism involved in the desorption process. We investigate the energetics and rate constants of three proposed mechanisms for H2 desorption from Si~100!231, namely, the prepairing mechanism, the isomerization mechanism, and the isolat...

Electronic excitation and dynamic promotion of a surface reaction.

The mechanism of recombinative desorption of hydrogen from a Ru(0001) surface induced by femtosecond-laser excitation has been investigated and compared to thermally initiated desorption. For the laser-driven process, it is shown that hot substrate electrons mediate the reaction within a few hundred femtoseconds resulting in a huge isotope effect between H2 and D2 in the desorption yield. In mi...

Investigation of the reliability of density functional methods: Reaction and activation energies for Si–Si bond cleavage and H2 elimination from silanes

In order to test the reliability of plane-wave and Gaussian-orbital based DFT methods for calculating reaction energies and activation barriers, detailed calculations are performed for several reactions involving gas phase silanes and a simple model of H2 desorption from the Si~100!231 surface. This study is motivated in particular by apparent discrepancies between the results of cluster-model ...

Direct pathway for sticking/desorption of H2 on Si(100).