Cluster modeling approach of a silicon surface using semiempirical methods

Abstract

When clusters are used as a model for the bulk or the surface in calculations, it is necessary to saturate the peripheral dangling bonds of boundary atoms. In this study, we employ flourine atoms and compare the results with the widely used practice where hydrogen atoms are used as terminal atoms. Using AM1 and PM3 semiempirical methods, surface reconstruction of Si(100) (2×1) is selected for test calculations. Effects of hydrogen and flourine terminal atoms are investigated for different sizes of clusters. Optimal strategies to model surface by clusters are discussed.