Determination of atom positions at stacking-fault dislocations on Au(111) by scanning tunneling microscopy

The determination of atom positions around Shockley-type partial dislocations [Burgers vector (1/6(1,1,-2)] at the (111) surface of gold has been achieved by operating a scanning tunneling microscope with atomic resolution on regions containing several unit cells of the (23× √3 ) stacking-fault reconstruction of this surface. The data show directly the occupation of both hexagonal-close-packed and face-centered-cubic sites in the surface layer, verifying earlier reconstruction models.