From Online Dictionary of Crystallography
Revision as of 12:56, 16 May 2017 by BrianMcMahon (Style edits to align with printed edition)
Configuration ponctuelle (Fr). Punktkonfiguration (Ge). Configurazione puntuale (It). 点配列(Ja).
The concept of point configuration is closely related to that of crystallographic orbit, but differs from it by the fact that point configurations are detached from their generating space groups. The concept of point configuration is the basis for the definition of lattice complexes.
Two crystallographic orbits are said to be configuration-equivalent if and only if their sets of points are identical. A point configuration is the set of all points that are common to a class of configuration-equivalent crystallographic orbits.
This definition uniquely assigns crystallographic orbits to point configurations but not vice versa.
The inherent symmetry of a point configuration is the most comprehensive space group that maps the point configuration onto itself. One crystallographic orbit out of each class of configuration-equivalent ones stands out because its generating space group coincides with the inherent symmetry of its point configuration.
Other terms used by different authors:
- regelmässiges Punktsystem
- regular system of points
- Chapter 220.127.116.11 of International Tables for Crystallography, Volume A, 6th edition