|
|
|
|
Snub cube
|
| |
|
| |
The snub cube, or snub cuboctahedron, is an Archimedean solid.
The snub cube has 38 faces, 6 of which are squares and the other 32 are equilateral triangles. It has 60 edges and 24 vertices. It is a chiral polyhedron, that is, it has two distinct forms, which are mirror images (or "enantiomorphs") of each other.
esian coordinates for the vertices of a snub cube are all the even permutations of
- (±1, ±ξ, ±1/ξ)
with an even number of plus signs, along with all the odd permutations with an odd number of plus signs, where ξ is the real solution to
- ξ3+ξ2+ξ=1,
which can be written
or approximately 0.543689.

Discussion
Ask a question about 'Snub cube'
Start a new discussion about 'Snub cube'
Answer questions from other users
|
Encyclopedia
The snub cube, or snub cuboctahedron, is an Archimedean solid.
The snub cube has 38 faces, 6 of which are squares and the other 32 are equilateral triangles. It has 60 edges and 24 vertices. It is a chiral polyhedron, that is, it has two distinct forms, which are mirror images (or "enantiomorphs") of each other.
Cartesian coordinates
Cartesian coordinates for the vertices of a snub cube are all the even permutations of
- (±1, ±ξ, ±1/ξ)
with an even number of plus signs, along with all the odd permutations with an odd number of plus signs, where ξ is the real solution to
- ξ3+ξ2+ξ=1,
which can be written
or approximately 0.543689. ξ is the reciprocal of the tribonacci constant. Taking the even permutations with an odd number of plus signs, and the odd permutations with an even number of plus signs, gives a different snub cube, the mirror image.
This snub cube has edges of length α, a number which satisfies the equation
- α6-4α4+16α2-32=0,
and can be written as
For a snub cube with unit edge length, use the following coordinates instead:
Geometric relations The snub cube can be generated by taking the six faces of the cube, pulling them outward so they no longer touch. Then give them all a small rotation on their centers (all clockwise or all counter-clockwise) until the spaces between can be filled with equilateral triangles.
Cube | Rhombicuboctahedron (Expanded cube) |
It can also be constructed as an alternation of a nonuniform great rhombicuboctahedron, deleting every other vertex and creating new triangles at the deleted vertices. A properly proportioned (nonuniform) great rhombicuboctahedron will create equilateral triangles at the deleted vertices. Depending on which set of vertices are alternated, the resulting snub cube can have a clockwise or counterclockwise twist.
-
See also
External links
- The Encyclopedia of Polyhedra
|
| |
|
|