Electron diffraction in the transmission electron microscopy (TEM) is a well-established and widely used technique in laboratories all over the world. In order to extract relevant crystallographic information, obtained diffraction patterns may require a significant amount of post-acquisition analysis. In order to meet this challenge, a computer program called CSpot (Fig. 1) was developed [1]. CSpot deals with three types of TEM diffraction patterns: spot, Kikuchi and ring (polycrystalline) diffraction patterns. The ability of the software to work with different types of diffraction patterns gives a user the possibility to cover a wide range of analyses and extract various information. CSpot allows for manipulation of simulated diffraction patterns in a real-time and interactive manner by changing and visualizing crystal orientation (e.g., pole figures) or adjusting simulation parameters. The main feature of the program is the ability to perform automatic indexing and crystal orientation determination using spot and Kikuchi diffraction patterns. When working with ring diffraction patterns, the user can present them in integral form, being analogues of X-Ray diffraction patterns and analyzed in a similar manner. CSpot operates on the information regarding microscope operating conditions (e.g., accelerating voltage, camera length, detector pixel size) and crystallographic structures. The software supports all space group symmetries and can work with Crystallography Open Database [2]. The software has built-in crystallographic calculators. CSpot is mainly dedicated to be a laboratory tool, helping in the analysis and interpretation of data. However, it can be also used as teaching aid. CSpot runs under Windows family operating system (XP or higher).
Figure 1. CSpot user interface
References
[1] Information on http://www.crystorient.com/
[2] Gražulis, S. Chateigner, D. Downs, R. T. Yokochi, A. F. T. Quirós, M. Lutterotti, L. Manakova, E. Butkus, J. Moeck, P. & Le Bail, A. (2009). Crystallography Open Database – an open-access collection of crystal structures. Journal of Applied Crystallography, 42, 726-729.
