Antiferromagnetic Ordering of Two Adjacent Dangling Bonds on Cl-terminated Si(001)

Abstract

We have performed spin-polarized density-functional theory calculations for two adjacent dangling bonds (DBs) on an otherwise Cl-terminated Si(001) surface. We consider the intradimer and interdimer configurations, where two DBs are within a single Si dimer and on one side of two adjacent Si dimers, respectively. Unlike the intradimer configuration showing a nonmagnetic ground state, the interdimer configuration is found to have an antiferromagnetic ground state. The different features of the scanning tunneling microscopy images for various bias voltages are discussed in connection with the band structure and the charge characters of the DBs.