The application of convergent-beam electron diffraction to the detection of small symmetry changes accompanying phase transformations I. General and methods

Abstract

Abstract This paper considers the origins of convergent-beam diffraction patterns (CBDPs) and the particular uses of high-order Laue zone (holz) lines which are a feature of these patterns. Small changes in the arrangement of the holz lines, corresponding to changes in the lattice parameter and symmetry of the crystal giving rise to them, are discussed, and a technique for their simulation described. The advantages and limitations of the convergent-beam diffraction technique are considered.