Solving a Long-Standing Problem Regarding Atomic Structure of Si(100)2x3-Ag

The atomic structure of the Si(100)2x3-Ag reconstruction has remained unknown for more than 25 years since its first observation with scanning tunneling microscopy, despite a relatively small unit cell and seeming abundance of the available experimental data. We propose a structural model of the Si(100)3x2-Ag reconstruction which comfortably fits all the principal experimental findings, including our own and those reported in the literature. The model incorporates 3 Si atoms and 4 Ag atoms per the 2 x 3 unit cell forming linear atomic chains along the 3aSi-periodic direction. A peculiar feature of the Si(100)2x3-Ag structure is the occurrence of the inner Si dimers in the second atomic layer from the top of the Si(100) substrate. The reconstruction is proved to possess semiconducting properties.

Automated summary

The Si(100)2x3-Ag reconstruction has a structural model with 3 Si atoms and 4 Ag atoms forming linear atomic chains along the 3aSi-periodic direction. A peculiar feature is the occurrence of inner Si dimers in the second atomic layer from the top of the Si(100) substrate. The reconstruction is confirmed to have semiconducting properties.