Principles of Trace Structure Analysis in Electron Microscopy

Structure analysis done with X-rays or with electrons, corresponds to an averaging of the specimen configuration over the exposure time. Such an analysis leads to the structure of the specimen only if the configuration does not change during exposure or if the change is negligible (stable molecule, crystal). Some time ago for instable configurations the method of "trace structure analysis" was proposed. The present paper explains the general principles of this method in detail. The static image of the structure will be divided into a dynamic succession of images along the time axis ("three-dimensional film"). But this division is not really characteristic for the method (it is in fact trivial). The main idea is to work with non-significant three-dimensional elementary structures and to use redundancies of the radiation induced physico-chemical processes for the combination of these elementary structures. Obviously these "redundancy laws" can only be unravelled in detail by trace structural work. It will be shown further that for special classes of these laws correlation analysis and pattern recognition procedures can be applied.