Point group
- Page ID
- 19076
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A point group is a group of symmetry operations all of which leave at least one point unmoved. A crystallographic point group is a point group that maps a point lattice onto itself: in three dimensions rotations and rotoinversions are restricted to 1, 2, 3, 4, 6 and \(\bar 1\), \(\bar 2\) (= m), \(\bar 3\), \(\bar 4\), \(\bar 6\) respectively.