Difference between revisions of "Subperiodic group"
From Online Dictionary of Crystallography
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A '''crystallographic subperiodic group''' in ''n''-dimensional space is a subperiodic group for which the group of linear parts is a crystallographic [[point group]] of ''n''-dimensional space. The crystallographic subperiodic groups in two and three-dimensional space are classified in: | A '''crystallographic subperiodic group''' in ''n''-dimensional space is a subperiodic group for which the group of linear parts is a crystallographic [[point group]] of ''n''-dimensional space. The crystallographic subperiodic groups in two and three-dimensional space are classified in: | ||
| − | *'''frieze groups''': 7 two-dimensional groups with one-dimensional translations; | + | *'''frieze groups''': 7 two-dimensional types of groups with one-dimensional translations; |
| − | *'''rod groups''': 75 three-dimensional groups with one-dimensional translations; | + | *'''rod groups''': 75 three-dimensional types of groups with one-dimensional translations; |
| − | *'''layer groups''': 80 three-dimensional groups with two-dimensional translations. | + | *'''layer groups''': 80 three-dimensional types of groups with two-dimensional translations. |
==See also== | ==See also== | ||
Revision as of 03:44, 26 November 2018
Groupe sous-périodique (Fr). Subperiodische Gruppe (Ge). Gruppo subperiodico (It). 亜周期群 (Ja). Groupo subperiódico (Sp).
A subperiodic group is a group of Euclidean mappings such that its translations form a lattice in a proper subspace of the space on which it acts.
A crystallographic subperiodic group in n-dimensional space is a subperiodic group for which the group of linear parts is a crystallographic point group of n-dimensional space. The crystallographic subperiodic groups in two and three-dimensional space are classified in:
- frieze groups: 7 two-dimensional types of groups with one-dimensional translations;
- rod groups: 75 three-dimensional types of groups with one-dimensional translations;
- layer groups: 80 three-dimensional types of groups with two-dimensional translations.
See also
- International Tables for Crystallography, Volume E