Cinematographic studies on the interaction of electrons with microcrystals of silver iodide

Abstract

Recent improvements in the design of electron microscopes leading to high resolution (ca. 10 Å) have resulted in the extended use of electron microscopy for the investigation of the internal structures of crystals and their imperfections (1, 2). It is essential for such observations that the crystals should be sufficiently thin for electron transmission to occur; an essential feature also for diffraction. In the case of silver halide crystals most investigations have been carried out on particles which appeared opaque to the electron beam. Such investigations are complicated, in the case of silver chloride and bromide, by the extensive decomposition which occurs. Silver iodide, however, is stable in the electron beam under controlled conditions and the preparation of thin microcrystalline plates of ß-AgI has enabled observations to be made on the internal changes occuring in the particles during electron irradiation (3). In view of the dynamic nature of these changes cinematography has been used to record them in detail.