Crystal Classes
The monoclinic crystal system class names, examples, Schönflies notation, Hermann-Mauguin notation, point groups, International Tables for Crystallography space group number, orbifold, type, and space groups are listed in the table below.
| # | Point group | Example | Type | Space groups | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Name | Schönflies | Intl | orbifold | Coxeter | |||||||||||
| 3-5 | monoclinic | C2 | 22 | + | halotrichite | enantiomorphic polar | |||||||||
| 6-9 | Domatic | C1h (=C1v = Cs) | *11 | hilgardite | polar | ||||||||||
| 10-15 | Prismatic | C2h | 2* | gypsum | centrosymmetric | ||||||||||
Sphenoidal is also monoclinic hemimorphic; Domatic is also monoclinic hemihedral; Prismatic is also monoclinic normal.
The three monoclinic hemimorphic space groups are as follows:
- a prism with as cross-section wallpaper group p2
- ditto with screw axes instead of axes
- ditto with screw axes as well as axes, parallel, in between; in this case an additional translation vector is one half of a translation vector in the base plane plus one half of a perpendicular vector between the base planes.
The four monoclinic hemihedral space groups include
- those with pure reflection at the base of the prism and halfway
- those with glide planes instead of pure reflection planes; the glide is one half of a translation vector in the base plane
- those with both in between each other; in this case an additional translation vector is this glide plus one half of a perpendicular vector between the base planes.
Read more about this topic: Monoclinic Crystal System
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