Model reconstructions for the Si„337... orientation

Although unstable, the Si 337 orientation has been known to appear in diverse experimental situations such as the nanoscale faceting of Si 112 , or in the case of miscutting a Si 113 surface. Various models for Si 337 have been proposed over time, which motivates a comprehensive study of the structure of this orientation. Such a study is undertaken in this article, where we report the results of a genetic algorithm optimization of the Si 337 2 1 surface. The algorithm is coupled with a highly optimized empirical potential for silicon, which is used as an efficient way to build a set of possible Si 337 models; these structures are subsequently relaxed at the level of ab initio density-functional methods. Using this procedure, we retrieve the 337 reconstructions proposed in previous works, as well as a number of different ones. © 2005 American Institute of Physics. DOI: 10.1063/1.2064309