Röntgentopographische und elektronenmikroskopische Untersuchung der Realstruktur von γ-In₂S₃-kristallen

Crystals of 7-In₂S₃, a new modification of indium sulphide, grown by vapour transport, were studied by X-ray topography (Lang technique) and electron microscopy. The most frequent defects are dislocations with Burgers vector of the type b= [100]. Growth layers were also observed. Neither the dissociation of dislocations into partials nor any stacking faults could be detected. γ-In₂S₃ gradually decomposes in the electron microscope by loss of sulphur. This results in an agglomeration of point defects leading to stacking faults surrounded by dislocation loops with b parallel to [001].