|Vertex configuration||(8) 4.6.6
|Symmetry group||D4h, [4,2], (*422), order 16|
|Rotation group||D4, [4,2]+, (422), order 8|
In geometry, the elongated dodecahedron, extended rhombic dodecahedron, or rhombo-hexagonal dodecahedron is a convex polyhedron with 8 rhombic and 4 hexagonal faces. The hexagons can be made equilateral, or regular depending on the shape of the rhombi. It can be seen as constructed from a rhombic dodecahedron elongated by a square prism. Along with the rhombic dodecahedron, it is a space-filling polyhedron.
- It can tesselate all space by translations.
- It is the Wigner-Seitz cell for certain body-centered tetragonal lattices.
This is related to the rhombic dodecahedral honeycomb with an elongation of zero. Projected normal to the elongation direction, the honeycomb looks like a square tiling with the rhombi projected into squares.
- Coxeter (1973) p.257
- Williamson (1979) p169
- Williams, Robert (1979). The Geometrical Foundation of Natural Structure: A Source Book of Design. Dover Publications, Inc. ISBN 0-486-23729-X. rhombo-hexagonal dodecahedron, p169
- H.S.M. Coxeter, Regular Polytopes, Third edition, (1973), Dover edition, ISBN 0-486-61480-8 p. 257