  The non-centrosymmetric semiconductors BiTeX (X = Cl, Br, I) show large
Rashba-type spin-orbit splittings in their electronic structure making them
candidate materials for spin-based electronics. However, BiTeI(0001) single
crystal surfaces usually consist of stacking-fault-induced domains of Te and I
terminations implying a spatially inhomogeneous electronic structure. Here we
combine scanning tunneling microscopy (STM), photoelectron spectroscopy (ARPES,
XPS) and density functional theory (DFT) calculations to systematically
investigate the structural and electronic properties of BiTeX(0001) surfaces.
For X = Cl, Br we observe macroscopic single-terminated surfaces. We discuss
chemical characteristics among the three materials in terms of bonding
character, surface electronic structure, and surface morphology.
