Atomic structure of the sb-induced (formula presented) surface: ab initio calculations

We present ab initio calculations on the atomic structure of the Sb-induced (Formula presented) surface. The scanning tunneling microscopy images of Si and Sb adatom structures are calculated and compared with recent experimental results. We demonstrate that the majority adatoms observed in the (Formula presented) structure are Sb atoms, supporting the recently proposed atomic model [Park et al., Phys. Rev. B 55, 9267 (1997)]. The origin of bias voltage-dependent scanning tunneling microscopy images is discussed.