three-fold rotation axis

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• Point groups in three dimensions — In geometry, a point group in three dimensions is an isometry group in three dimensions that leaves the origin fixed, or correspondingly, an isometry group of a sphere. It is a subgroup of the orthogonal group O(3), the group of all isometries… …   Wikipedia

• Dihedral symmetry in three dimensions — This article deals with three infinite sequences of point groups in three dimensions which have a symmetry group that as abstract group is a dihedral group Dihn ( n ≥ 2 ). See also point groups in two dimensions. Chiral: Dn (22n) of… …   Wikipedia

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• Molecular symmetry — in chemistry describes the symmetry present in molecules and the classification of molecules according to their symmetry. Molecular symmetry is a fundamental concept in chemistry, as it can predict or explain many of a molecule s chemical… …   Wikipedia

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• Island Three — For fictional structures for living in space, see Space stations and habitats in popular culture. Artist s depiction of a pair of O Neill cylinders. The O Neill cylinder (also called an Island Three habitat) is a space settlement design proposed… …   Wikipedia

• Crystallographic point group — In crystallography, a crystallographic point group is a set of symmetry operations, like rotations or reflections, that leave a central point fixed while moving other directions and faces of the crystal to the positions of features of the same… …   Wikipedia

• Dihedral group of order 6 — The smallest non abelian group has 6 elements. It is a dihedral group with notation D3 (or D6, both are used) and the symmetric group of degree 3, with notation S3. This page illustrates many group concepts using this group as example. Contents 1 …   Wikipedia

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• Cyclic symmetries — This article deals with the four infinite series of point groups in three dimensions (n≥1) with n fold rotational symmetry about one axis (rotation by an angle of 360°/n does not change the object), and no other rotational symmetry (n=1 covers… …   Wikipedia