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Dodecahedron-Icosahedron Compound


DodecahedronIcosahedronCompound

The dodecahedron-icosahedron compound is a polyhedron compound consisting of a dodecahedron and its dual the icosahedron. In the compound, the dodecahedron and icosahedron are rotated pi/5 radians with respect to each other, and the ratio of the icosahedron to dodecahedron edges lengths are the golden ratio phi.

It is implemented in the Wolfram Language as PolyhedronData["DodecahedronIcosahedronCompound"].

Dodecahedron-IcosahedronCompoundNet

Its hull is most easily constructed by adding 20 triangular pyramids to an icosahedron. If the dodecahedron is chosen to have unit edge length, the resulting compound has side lengths

s_1=1/2
(1)
s_2=1/4(1+sqrt(5)).
(2)

The surface area and volume of the resulting hull are

S=(15)/4sqrt(13+5sqrt(5)+sqrt(150+66sqrt(5)))
(3)
V=5/(16)(15+7sqrt(5)).
(4)
DodecahedronIcosahedronCompoundIntersectionsAndConvexHulls

The interior is an icosidodecahedron, making the faces of the dodecahedron-icosahedron compound a stellation of the icosidodecahedron. The intersecting edges of the compound form the polyhedron diagonals of the 30 rhombuses constituting the rhombic triacontahedron (Ball and Coxeter 1987), which is the convex hull of the compound.


See also

Dual Polyhedron, Dodecahedron, Icosahedron, Icosidodecahedron, Platonic Solid, Polyhedron Compound, Rhombic Triacontahedron

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References

Cundy, H. and Rollett, A. "Dodecahedron Plus Icosahedron." §3.10.3 in Mathematical Models, 2nd ed. Stradbroke, England: Tarquin Pub., p. 131, 1989.Wenninger, M. J. "First Stellation of the Icosidodecahedron." §47 in Polyhedron Models. Cambridge, England: Cambridge University Press, p. 76, 1989.

Cite this as:

Weisstein, Eric W. "Dodecahedron-Icosahedron Compound." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Dodecahedron-IcosahedronCompound.html

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