Different STM images of the superstructure on a clean Si(133)-6 × 2 surface

New detailed scanning tunneling microscopy images of the superstructure on an atomically clean Si(133)-6 × 2 surface are obtained. Similarities and differences with previously reported images are discussed. On the basis of these data, a new atomic model for the unit cell of the superstructure on the Si(133)-6 × 2 surface is suggested taking into account inconsistencies in the previously proposed models.