Difference between revisions of "Crystal system"
From Online Dictionary of Crystallography
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| + | <font color="blue">Système cristallin </font>(''Fr''). <Font color="black"> Sistema cristallino </Font>(''It'') | ||
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== Definition == | == Definition == | ||
| − | + | A crystal-class system, or '''crystal system''' for short, contains complete [[geometric crystal class]]es of space groups. All those geometric crystal classes belong to the the same crystal system which intersect exactly the same set of [[Bravais flock]]s. | |
| + | == Crystal systems in two and three dimensions == | ||
| + | In the two-dimensional space there exist four crystal systems: | ||
| + | * monoclinic | ||
| + | * orthorhombic | ||
| + | * tetragonal | ||
| + | * hexagonal | ||
| + | |||
| + | In the three-dimensional space there exist seven crystal families: | ||
* triclinic | * triclinic | ||
* monoclinic | * monoclinic | ||
| − | * orthorhombic | + | * orthorhombic |
* tetragonal | * tetragonal | ||
* trigonal | * trigonal | ||
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* cubic | * cubic | ||
| − | Note that rhombohedral crystals belong to the trigonal system. | + | Note that the adjective ''rhombohedral'' refers to a [[lattice system]], not to a crystal system. Rhombohedral crystals belong to the trigonal system, but trigonal crystals may belong to the rhombohedral or to the hexagonal [[lattice system]]. |
| − | [[category: | + | |
| + | == See also == | ||
| + | Section 8.2.8 in of ''International Tables of Crystallography, Volume A'' | ||
| + | |||
| + | [[category: Fundamental crystallography]] | ||
Revision as of 15:29, 23 February 2007
Système cristallin (Fr). Sistema cristallino (It)
Definition
A crystal-class system, or crystal system for short, contains complete geometric crystal classes of space groups. All those geometric crystal classes belong to the the same crystal system which intersect exactly the same set of Bravais flocks.
Crystal systems in two and three dimensions
In the two-dimensional space there exist four crystal systems:
- monoclinic
- orthorhombic
- tetragonal
- hexagonal
In the three-dimensional space there exist seven crystal families:
- triclinic
- monoclinic
- orthorhombic
- tetragonal
- trigonal
- hexagonal
- cubic
Note that the adjective rhombohedral refers to a lattice system, not to a crystal system. Rhombohedral crystals belong to the trigonal system, but trigonal crystals may belong to the rhombohedral or to the hexagonal lattice system.
See also
Section 8.2.8 in of International Tables of Crystallography, Volume A