The twin statistic calculated here is based on local intensity differences making it less sensitive to phenomena that tend to confound traditional intensity statistics, such as anisotropic diffraction and pseudo-centering.
Reference: J. Padilla & T. O. Yeates. A statistic for local intensity differences: robustness to anisotropy and pseudo-centering and utility for detecting twinning. Acta Crystallogr. D59, 1124-30, 2003.
This twinning test was implemented with the program "dataman" available from the Uppsala Software Factory.
This is Version 3. Version 2 can be found here.
Comments and Questions on the Twinning Server may be sent to: yeates at mbi.ucla.edu
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