Atomic-scale structure of the SrTiO3(001)-c(6x2) reconstruction: Experiments and first-principles calculations

The c(6x2) is a reconstruction of the SrTiO3(001) surface that is formed between 1050 and 1100 degrees C in oxidizing annealing conditions. This work proposes a model for the atomic structure for the c(6x2) obtained through a combination of results from transmission electron diffraction, surface x-ray diffraction, direct methods analysis, computational combinational screening, and density functional theory. As it is formed at high temperatures, the surface is complex and can be described as a short-range-ordered phase featuring microscopic domains composed of four main structural motifs. Additionally, nonperiodic TiO2 units are present on the surface. Simulated scanning tunneling microscopy images based on the electronic structure calculations are consistent with experimental images