Schmidt, Søren

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 19, 2017An algorithm for determining crystal lattices in unknown polycrystalline compoundsSchmidt, SørenPublication date:2009Link back to DTU OrbitCitation (APA):Schmidt, S. (2009). An algorithm for determining crystal lattices in unknown polycrystalline compounds. Abstractfrom Total Cryst Workshop, Grenoble (FR), 1-3 Apr., .Total Cryst Workshop   An algorithm for determining crystal lattices in unknown polycrystalline compounds  Søren Schmidt  Risø DTU - Technical University of Denmark   When recovering crystallographic orientations of individual grains in polycrystalline materials both unit cell parameters and Bravais lattice are utilized. These crystallographic properties are normally determined from the radial spectra of diffraction rings by Power Diffraction Indexing programs. Afterwards, grains are located in reciprocal space by identifying replica of the Bravais lattice [1,2].   Here, a new method is presented for determining the crystallographic properties of unknown polycrystalline compounds. Effectively, the method reduces the polycrystalline data set into a single crystal data set. As the Bravais lattice is embedded multiple times in the data set (multiplicity is given by number of grains) the method seeks to recover the base lattice by rotating the whole data set and match it against itself. If, by chance, the rotation is close to the crystallographic mis-orientation between two grains the algorithm identifies the two lattices. A match against previously identified lattice solutions is made. Clearly, the probability of making a false match in either selection step is high. In the algorithm a number of filtering steps ensures that the final estimation of the base lattice is only constructed from high frequency lattice points. The unit cell and Bravais lattice can then be determined from the base lattice by a single crystal indexing program. The algorithm itself is implemented in [2]. The algorithm and results will be presented.   References [1] J. Wright, http://fable.wiki.sourceforge.net/imaged11 [2] S. Schmidt, http://fable.wiki.sourceforge.net/GrainSpotter  -18- 

An algorithm for determining crystal lattices in unknown polycrystalline compounds

http://orbit.dtu.dk/ws/files/6392853/Schmidt_abstract.pdf

An algorithm for determining crystal lattices in unknown polycrystalline compounds

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology