The tetrahedron, cube, and octahedron all occur naturally in crystal structures.
From the en.wikipedia.org
Other Platonic solids include the tetrahedron, the octahedron, the icosahedron.
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The truncated octahedron is one of five three-dimensional primary parallelohedra.
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The six nitrogen atoms are at the corners of an octahedron around the Fe atom.
From the sciencedaily.com
Truncating edges down to points produces the octahedron as a rectified tetahedron.
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Since each of its faces has point symmetry the truncated octahedron is a zonohedron.
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These assembled into the truncated octahedron by forming 72 hydrogen bonds.
From the newscientist.com
Three, the tetrahedron, octahedron and icosahedron, have triangular faces.
From the economist.com
It gets its name from the fact that it is both a rectifiedcube and a rectified octahedron.
From the en.wikipedia.org
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Any polyhedron having eight plane faces
In geometry, an octahedron (plural: octahedra) is a polyhedron with eight faces. A regular octahedron is a Platonic solid composed of eight equilateral triangles, four of which meet at each .
Octahedron is the fifth full-length studio album by American progressive rock band The Mars Volta, released on June 23, 2009. The album was released by Warner Bros. Records in North America and Mercury Records worldwide. ...
(octahedral) A molecular structural shape in which 6 atoms or groups of atoms are symmetrically arranged around a central atom. The positions of the 6 surrounding atoms define the vertices of an octahedron.
(Octahedral) Octa- signifies eight, and -hedral relates to a surface, so octahedral almost literally means "eight surfaces." The bond angle is 90 degrees. An example of an octahedral molecule is sulfur hexafluoride (SF6).
(octahedral) relating to a geometric arrangement of six ligands equally distributed around a Lewis acid; literally, eight faces
A solid figure contained by 8 equal and equilateral triangles.
(n) A regular Platonic polyhedron consisting of 6 vertices, connected by 12 edges to form 8 triangular faces all with equal areas, angles and edge lengths.
Any figure having eight sides or faces. In the case of a diamond, the diamond crystals that make a diamond are usually in the form of a Octahedron.