TY - JOUR
ID - Digital.CSIC
A1 - Riikonen, Sampsa
A1 - Sánchez-Portal, Daniel
Y1 - 2008-04-17
SN - 1098-0121
UR - http://hdl.handle.net/10261/8485
N2 - We present here a comprehensive search for the structure of the Si(553)-Au reconstruction. More than 200 different trial structures have been studied using first-principles density-functional calculations with the SIESTA code. An iterative procedure, with a step-by-step increase in the accuracy and computational cost of the calculations, was used to allow for the study of this large number of configurations. We have considered reconstructions restricted to the topmost bilayer and studied two types: (i) "flat" surface-bilayer models, where atoms at the topmost bilayer present different coordinations and registries with the underlying bulk, and (ii) nine different models based on the substitution of a silicon atom by a gold atom in different positions of a ?-bonded chain reconstruction of the Si(553) surface. We have developed a compact notation that allows us to label and identify all these structures. This is very useful for the automatic generation of trial geometries and for counting the number of inequivalent structures, i.e., structures that have different bonding topologies. The most stable models are those that exhibit a honeycomb-chain structure at the step edge. One of our models (model "f2") reproduces the main features of the room temperature photoemission and scanning-tunneling microscopy data. Thus, we conclude that this model is a good candidate for the high temperature structure of the Si(553)-Au surface.
PB - American Physical Society
KW - Bonds (chemical)
KW - Density functional theory
KW - Gold
KW - Iterative methods
KW - Photoemission
KW - Scanning tunnelling microscopy
KW - Silicon
KW - Surface reconstruction
KW - Surface structure
T1 - Systematic investigation of the structure of the Si(553)-Au surface from first principles
ER -