  The structural and electronic properties of Si(335)-Au surface decorated with
Pb atoms are studied by means of density-functional theory. The resulting
structural model features Pb atoms bonded to neighboring Si and Au surface
atoms, forming monoatomic chain located 0.2 nm above the surface. The presence
of Pb chain leads to a strong rebonding of Si atoms at the step edge. The fact
that Pb atoms occupy positions in the middle of terrace is consistent with STM
data, and also confirmed by simulated STM images. The calculated band structure
clearly shows one-dimensional metallic character. The calculated electronic
bands remain in very good agreement with photoemission data.
