Dyakis dodecahedron
Non-uniform polyhedron with 24 chiral trapezoid faces / From Wikipedia, the free encyclopedia
In geometry, the dyakis dodecahedron /ˈdʌɪəkɪsˌdəʊdɪkəˈhiːdrən/[1] or diploid is a variant of the deltoidal icositetrahedron with pyritohedral symmetry, transforming the kite faces into chiral quadrilaterals. It is the dual of the cantic snub octahedron. It can be constructed by enlarging 24 of the 48 faces of the disdyakis dodecahedron, and is inscribed in the dyakis dodecahedron,[2] thus it exists as a hemihedral form of it with indices {hkl}.[3] It can be constructed into two non regular pentagonal dodecahedra, the pyritohedron and the tetartoid. The transformation to the pyritohedron can be made by combining two adjacent trapezoids that share a long edge together into one hexagon face, which is a pyritohedral pentagon with an extra vertex added. The edges that bend at it can be combined and the vertex removed to finally get the pentagon. The transformation to the tetartoid can be made by enlarging 12 of the dyakis dodecahedron's 24 faces.
Dyakis dodecahedron | |
---|---|
(rotating and 3D model) | |
Type | Non-uniform |
Face polygon | Chiral quadrilateral with 2 unequal acute angles & 2 unequal obtuse angles |
Faces | 24, congruent |
Edges | 48 |
Vertices | 26 |
Face configuration | V3.4.4.4 |
Symmetry group | Pyritohedral |
Dual polyhedron | Cantic snub octahedron |
Properties | convex, face-transitive |
Since the quadrilaterals are chiral and non-regular, the dyakis dodecahedron is a non-uniform polyhedron, a type of polyhedron that isn't vertex transitive and doesn't have regular polygon faces. Since it is face-transitive, it is an isohedron.[4] The name diploid derives from the Greek word διπλάσιος (diplásios), meaning twofold since it has 2-fold symmetry along its 6 octahedral vertices. It has the same number of faces, edges and vertices as the deltoidal icositetrahedron as they are topologically identical.