Decoration of Strain Bands with F‐Centres in Potassium Chloride Crystals Deformed by Indentation

It is shown that the strain bands introduced into potassium chloride crystals by an indentor can be decorated with F‐centres in a simple procedure involving coloration by ionizing radiation and optical bleaching. The method reveals the existence of strain bands distributed along 〈110〉, 〈111〉, and 〈120〉 directions. On assuming that the macroscopic accumulations of vacancies responsible for the above effect are due to dislocations intersecting each other the formation of 〈120〉 bands necessitates the operation of {112} 〈110〉 or {122} 〈110〉 glide systems in which the screw dislocations are moving.