Sep 19 – 22, 2022
Paul Scherer Institute, Villigen, Switzerland
Europe/Zurich timezone

diffcalc-core: Diffraction condition calculation package for a six-circle diffractometer

Sep 20, 2022, 5:52 PM
WHGA/Auditorium and online (Paul Scherer Institute, Villigen, Switzerland)

WHGA/Auditorium and online

Paul Scherer Institute, Villigen, Switzerland

Paul Scherrer Institute Forschungsstrasse 111 CH-5232-Villigen-PSI
Poster NOBUGS 2022


Irakli Sikharulidze (Diamond Light Source)


The Python 3 package diffcalc-core implements diffraction condition calculation for a six-circle x-ray diffractometer according to the methodology described in H. You. Angle calculations for a ‘4S+2D’ six-circle diffractometer. J. Appl. Cryst. (1999). 32, 614-623. Diffractometer operation modes are selected based on three constraints that can include combination of detector, sample, reference vector, scattering plane, incident, exit beam or χ-plane orientations. All solutions fulfilling the diffractometer equation are returned for a requested reciprocal orientation. Configurations that correspond to a continuous solution space are flagged as insufficiently constrained. UB matrix can be set directly or calculated using reference reflections and/or known crystal orientations. Methods are provided to refine UB matrix based on a single reflection data or using a least-square fitting procedure with data from multiple reflections. The package source is available on GitHub ( under terms of Apache Software License ver. 2.0.

Email address of presenting author

Primary author

Irakli Sikharulidze (Diamond Light Source)

Presentation materials