Translation‐permutation operator algebra for the description of crystal structures. II. Interstice lattice stacking faults

Interstice lattice stacking faults (ILSF) are predicted for all crystal structures that are composed of both (a) anion lattices that are ideally closest packed and (b) cation interstice lattices that are only partially occupied. For brevity, theoretical examples are given only for the ZnS, CdX~, and spinel structures. Translation-permutation operator representations are presented for basal and prismatic ILSF which respectively lie perpendicular and parallel to the stacking axis, and for pyramidal ILSF which are tilted with respect to the c axis. Local charge unbalance occurs in both the basal and prismatic ILSF, and the basal ILSF also exhibits a local non-stoichiometry. Experimental examples of isolated ILSF in BeO bicrystals are presented.