Surfaces of Intermetallics: Quasicrystals and Beyond
The goal of this work is to characterize surfaces of intermetallics, including quasicrystals. We can determine the surface composition and surface structure of these materials by using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM) under ultrahigh vacuum conditions. We apply these techniques generally on clean surfaces, but in some cases, we can also apply these techniques after an adsorption of a molecule or a metal on surfaces as well. In this dissertation, five chapters focus on characterizing clean surfaces and other types of systems on surfaces. They are (1) Weak bonding of Zn in an Al-Based approximant, based on surface measurements; (2) Structure of the clean Gd5Ge4 (010) surface; (3) Preferential surface oxidation of Gd in Gd5Ge4; (4) The interaction of Au on the binary NiAl (110) surface; and (5) A comparison of the Ag and Au structures on NiAl (110) using XPD and STM.