Perfect planar antiphase-domain structures: a shift-lattice interpretation

Abstract

Abstract The principle of the shift lattice has been employed to re-interpret the structures and Fourier transforms of materials containing regular arrays of planar antiphase domains which lie perpendicular to one principal axis of an orthorhombic matrix. The results are illustrated with reference to the alloy phases CuAu II and Ag3Mg. The former application is a straightforward shift-lattice interpretation. In the latter, however, the basic g-functions in real space are of non-zero value for so short a distance (less than two unit subcells) that their Fourier transforms, the G-functions in reciprocal space, overlap considerably; in this case, the analysis that has to be performed to reveal the basic G-functions (and hence their inverse transforms, the g-functions) is described. The application of the method is compared with other conventional approaches.