Quantitative atomic-scale analysis of interface structures: Transmission electron microscopy and local density functional theory

Transmission electron microscopy (TEM) and local density functional theory (LDFT) are combined to analyze the microscopic structure of the rhombohedra l twin interface in alpha -Al2O3. LDFT provides interfacial energetics and atomic and electronic structures for three competing models. With high-reso lution TEM the atomic structure at the interface is imaged quantitatively a long two orthogonal zone axis. Electron energy loss spectroscopy in TEM wit h nanoscale spatial resolution yields the interfacial electronic structure. Both experiments confirm the theoretically preferred model quantitatively.