Ceramics information from diffraction

The wavelike nature of electrons enables electron diffraction studies of materials. Most electron diffraction patterns are obtained in a transmission electron microscope, which allows us to obtain structural information from very small regions. This is of particular importance in many new ceramics where we are often dealing with thin interface layers (such as at grain boundaries) and very small grains (nanopowders). 

If the scattered beam is a sharp spot diffracted from a single crystal, the phase contrast image when it is recombined is an image of the crystal lattice. This specialized phase contrast technique is applied to the study of atomic scale structure in crystalline specimens of metals and ceramics. It has only rarely been applied to the study of polymer materials due primarily to their instability in the electron beam. Lattice images have been obtained from radiation stable aromatic molecules, such as the liquid crystalline polymers (Section 5.6). They have shown important information regarding the ordered structure. 

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