AB INITIO DYNAMICS OF SURFACE CHEMISTRY

Supplemental Material

Supplementary Data

• Figure 1. Top view of a Si(100) surface that has been exposed to fluorine gas in an ab initio--derived MD simulation. The grayish white spheres are F atoms, the top layer of Si is depicted as pink spheres, while the rest (blue spheres) are subsurface Si. Note the presence of SiF, SiF2, and SiF3 groups on the surface, even at the low coverage of 1.1 monolayers, and the initial onset of disorder, as illustrated by the disruption of the (pink) Si dimer rows. [Adapted from Reference 31a (Weakliem PC, Wu CJ, Carter EA. 1992. Phys. Rev. Lett. 69:200--3).]

  

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  Figure 2. Snapshots from a fully ab initio MD simulation of H2 desorbing from Si(100), starting from the transition state for desorption via a dihydride desorption precursor. The H atoms are the small magenta spheres, the light blue spheres are silicon atoms, and the dark blue spheres are embedding atoms. Note that while the structure of the transition state (t = 0) would suggest a very broad angular distribution, the corrugated nature of the surface allows the H2 to scatter off of a neighboring dimer and become refocused more toward the surface normal. [From Reference 91 (da Silva AJr., Radeke MR, Carter EA. 1997. Surf. Sci. Lett. 381:628--35).]