Small rhombidodecacron

In geometry, the small rhombidodecacron is a nonconvex isohedral polyhedron. It is the dual of the small rhombidodecahedron. It is visually identical to the Small dodecacronic hexecontahedron. It has 60 intersecting antiparallelogram faces.

Small rhombidodecacron
Type	Star polyhedron
Face
Elements	F = 60, E = 120 V = 42 (χ = −18)
Symmetry group	Ih, [5,3], *532
Index references	DU39
dual polyhedron	Small rhombidodecahedron

3D model of a small rhombidodecacron

Proportions

Each face has two angles of ${\displaystyle \arccos({\frac {5}{8}}+{\frac {1}{8}}{\sqrt {5}})\approx 25.242\,832\,961\,52^{\circ }}$ and two angles of ${\displaystyle \arccos(-{\frac {1}{2}}+{\frac {1}{5}}{\sqrt {5}})\approx 93.025\,844\,508\,96^{\circ }}$. The diagonals of each antiparallelogram intersect at an angle of ${\displaystyle \arccos({\frac {1}{4}}+{\frac {1}{10}}{\sqrt {5}})\approx 61.731\,322\,529\,52^{\circ }}$. The ratio between the lengths of the long edges and the short ones equals ${\displaystyle {\frac {1}{2}}+{\frac {1}{2}}{\sqrt {5}}}$, which is the golden ratio. The dihedral angle equals ${\displaystyle \arccos({\frac {-19-8{\sqrt {5}}}{41}})\approx 154.121\,363\,125\,78^{\circ }}$.

References

• Wenninger, Magnus (1983), Dual Models, Cambridge University Press, ISBN 978-0-521-54325-5, MR 0730208

External links

• Weisstein, Eric W. "Small rhombidodecacron". MathWorld.
• Uniform polyhedra and duals