Electron diffraction from microtwins and long-period polytypes

Abstract

It has been shown that rows of spots can be produced in a selected-area electron diffraction pattern from a microtwin of width up to ∼18·5nm. The spacing of the spots has been shown to be equal to the inverse of the twin plane spacing. The observation is directly analogous to the classical experiment in light optics. A similar effect can occur for a long-period structure, as illustrated by βm-Al₂O₂.