Y. Ma et al., REFLECTION HIGH-ENERGY ELECTRON-DIFFRACTION ANALYSIS OF THE SI(111)-(7X7) RECONSTRUCTION, Physical review. B, Condensed matter, 49(24), 1994, pp. 17448-17451
Most of the techniques used to determine the structure of reconstructe
d surfaces are relatively insensitive to displacements perpendicular t
o the surface, especially those of subsurface atoms. Reflection high-e
nergy electron diffraction (RHEED) is sensitive to these displacements
. We have performed a dynamical simulation of RHEED intensities and sh
ow that for the Si(111)-7 X 7 reconstruction, the dimer-adatom stackin
g-fault model optimized by ab initio parallel computation has given mo
re accurate atomic Positions than previous determinations by other app
roaches. This indicates that the relative intensities of reflections i
n a RHEED pattern contain important, sensitive surface structural info
rmation.