Electron Diffraction Tomography and Dynamical Refinement for Crystal-Structure Characterization of Nanocrystalline Materials
Abstract
Three-dimensional electron diffraction tomography allows one to obtain structure information from nanocrystals. However, in order to get accurate results the dynamical theory must be used due to the strong dynamical interaction between electrons and matter.
Full structure refinement using dynamical theory has been in use for some time, in spite of being hampered by the fact that the intensities are very sensitive to variations of thickness and of the orientation of the sample. A remedy to this problem is the technique called precession electron diffraction.
The use of precession electron diffraction in combination with electron diffraction tomography results in more accurate structure parameters and lower figures of merit in the structure refinement. The principles of electron diffraction tomography, precession electron diffraction and dynamical refinement will be demonstrated on the structural analysis of a nanowire of Ni3Si2.