VI. The growth of cadmium iodide crystals: I—Dislocations and spiral growth

Abstract

Summary Evidence is given that cadmium iodide crystals grow from a low degree of supersaturation by the dislocation mechanism. Sequences of photographs illustrate the stages in the growth of the crystal plates. The screw dislocations are not simple but are groups of simple dislocations. The kinking of step-lines is explained by the interaction of screw dislocation groups of different strengths. The properties of large screw dislocation groups in the crystal plates are discussed.