Structure determination of Tl/Ge(111)-(3 x 1) by surface x-ray diffraction

We have determined the structure of the Tl/Ge(111)-(3 x 1) surface by surface x-ray diffraction (SXRD). A Patterson function indicates the honeycomb-chain channel (HCC) structure, which is a common framework of alkali-metal-induced (3 x 1) surfaces on Si(111) and Ge(111). We examined the HCC models with different Tl adsorption sites of H3 and T4 and found significant differences in the simulated fractional-order rods. The HCC structure with Tl at H3 shows good agreement with the experimental data. The optimized HCC structure for SXRD is consistent with the first-principles calculation and angle-resolved photoemission studies