Electron Damage and Defects in Organic Crystals.

摘要

The nature of the defects discernable from and the radiation damage that is induced by high resolution electron microscopy is reported. The structural aspects of the radiation damage process can be correlated to the expected radiochemical decomposition of these materials and these effects identified. The types of local defect formed by radiation damage are often clearly distinguishable,in high resolution images,from those inherent in the microstructure. Techniques used in this type of electron microscopy and the limitations imposed by radiation damage are described as are the relevant radiochemical characteristics of these processes. In copper pthalocyanine,microstructural features distinct from those induced by radiation damage were identified which are consistent with those predicted and described by other workers in similar materials. The high resolution studies indicate that some of the microstructures observed are caused by structural rearrangements that can account,to some extent,for additional crystallographic forms that have been identified in this material and the photochemical behaviour of related structures. (ERA citation 02:014326)