Disdyakis triacontahedron
Disdyakis triacontahedron
Click on picture for large version

spinning version

Type Catalan
Coxeter diagram
Face polygon scalene triangle
Faces 120
Edges 180
Vertices 62 = 12 + 20 + 30
Face configuration V4.6.10
Symmetry group Ih, H3, [5,3], (*532)
Rotation group I, [5,3]+, (532)
Dihedral angle 164° 53' 17"
Dual polyhedron truncated icosidodecahedron
Properties convex, face-transitive
Disdyakis triacontahedron
Net

In geometry, a disdyakis triacontahedron, or hexakis icosahedron is a Catalan solid with 120 faces and the dual to the Archimedean truncated icosidodecahedron. As such it is face uniform but with irregular face polygons. It looks a bit like an inflated rhombic triacontahedron—if one replaces each face of the rhombic triacontahedron with a single vertex and four triangles in a regular fashion one ends up with a disdyakis triacontahedron. That is, the disdyakis triacontahedron is the Kleetope of the rhombic triacontahedron. It also has the most faces among the Archimedean and Catalan solids, with the snub dodecahedron, with 92 faces, in second place.

The edges of the polyhedron projected onto a sphere form great circles, and represent all ten mirror planes of reflective Ih icosahedral symmetry, as shown in this image. Combining pairs of light and dark triangles define the fundamental domains of the nonreflective I icosahedral symmetry.

Related polyhedra

It is topologically related to a polyhedra sequence defined by the face configuration V4.6.2n. This group is special for having all even number of edges per vertex and form bisecting planes through the polyhedra and infinite lines in the plane, and continuing into the hyperbolic plane for any

With an even number of faces at every vertex, these polyhedra and tilings can be shown by alternating two colors so all adjacent faces have different colors.

Each face on these domains also corresponds to the fundamental domain of a symmetry group with order 2,3,n mirrors at each triangle face vertex.

n 2 3 4 5
Tiling space Spherical
Face configuration
V4.6.2n
V4.6.4 V4.6.6 V4.6.8 V4.6.10
Symmetry group
(Orbifold)
D3h [2,3], (*322)
D6h (*622) full sym.
Td [3,3] (*332)
Oh (*432) full sym.
Oh [4,3] (*432) Ih [5,3] (*532)
Symmetry
fundamental
domain

(Order 12)

(Order 24)

(Order 48)

(Order 60)
Polyhedron
Coxeter diagram
Net

References