Table of polyhedron dihedral angles

From HandWiki

The dihedral angles for the edge-transitive polyhedra are:

Picture Name Schläfli
symbol
Vertex/Face
configuration
exact dihedral angle
(radians)
dihedral angle
– exact in bold,
else approximate
(degrees)
Platonic solids (regular convex)
Tetrahedron {3,3} (3.3.3) arccos (⁠1/3⁠) 70.529°
Hexahedron or Cube {4,3} (4.4.4) arccos (0) = ⁠π/2⁠ 90°
Octahedron {3,4} (3.3.3.3) arccos (-⁠1/3⁠) 109.471°
Dodecahedron {5,3} (5.5.5) arccos (-⁠√5/5⁠) 116.565°
Icosahedron {3,5} (3.3.3.3.3) arccos (-⁠√5/3⁠) 138.190°
Kepler–Poinsot solids (regular nonconvex)
Small stellated dodecahedron {⁠5/2⁠,5} (⁠5/2⁠.⁠5/2⁠.⁠5/2⁠.⁠5/2⁠.⁠5/2⁠) arccos (-⁠√5/5⁠) 116.565°
Great dodecahedron {5,⁠5/2⁠} ⁠(5.5.5.5.5)/2⁠ arccos (⁠√5/5⁠) 63.435°
Great stellated dodecahedron {⁠5/2⁠,3} (⁠5/2⁠.⁠5/2⁠.⁠5/2⁠) arccos (⁠√5/5⁠) 63.435°
Great icosahedron {3,⁠5/2⁠} ⁠(3.3.3.3.3)/2⁠ arccos (⁠√5/3⁠) 41.810°
Quasiregular polyhedra (Rectified regular)
Tetratetrahedron r{3,3} (3.3.3.3) arccos (-⁠1/3⁠) 109.471°
Cuboctahedron r{3,4} (3.4.3.4) arccos (-⁠√3/3⁠) 125.264°
Icosidodecahedron r{3,5} (3.5.3.5) arccos⁡(−11575+305) 142.623°
Dodecadodecahedron r{⁠5/2⁠,5} (5.⁠5/2⁠.5.⁠5/2⁠) arccos (-⁠√5/5⁠) 116.565°
Great icosidodecahedron r{⁠5/2⁠,3} (3.⁠5/2⁠.3.⁠5/2⁠) arccos⁡(11575+305) 37.377°
Ditrigonal polyhedra
Small ditrigonal icosidodecahedron a{5,3} (3.⁠5/2⁠.3.⁠5/2⁠.3.⁠5/2⁠)
Ditrigonal dodecadodecahedron b{5,⁠5/2⁠} (5.⁠5/3⁠.5.⁠5/3⁠.5.⁠5/3⁠)
Great ditrigonal icosidodecahedron c{3,⁠5/2⁠} ⁠(3.5.3.5.3.5)/2⁠
Hemipolyhedra
Tetrahemihexahedron o{3,3} (3.4.⁠3/2⁠.4) arccos (⁠√3/3⁠) 54.736°
Cubohemioctahedron o{3,4} (4.6.⁠4/3⁠.6) arccos (⁠√3/3⁠) 54.736°
Octahemioctahedron o{4,3} (3.6.⁠3/2⁠.6) arccos (⁠1/3⁠) 70.529°
Small dodecahemidodecahedron o{3,5} (5.10.⁠5/4⁠.10) arccos⁡(115195−65) 26.058°
Small icosihemidodecahedron o{5,3} (3.10.⁠3/2⁠.10) arccos (-⁠√5/5⁠) 116.56°
Great dodecahemicosahedron o{⁠5/2⁠,5} (5.6.⁠5/4⁠.6)
Small dodecahemicosahedron o{5,⁠5/2⁠} (⁠5/2⁠.6.⁠5/3⁠.6)
Great icosihemidodecahedron o{⁠5/2⁠,3} (3.⁠10/3⁠.⁠3/2⁠.⁠10/3⁠)
Great dodecahemidodecahedron o{3,⁠5/2⁠} (⁠5/2⁠.⁠10/3⁠.⁠5/3⁠.⁠10/3⁠)
Quasiregular dual solids
Rhombic hexahedron
(Dual of tetratetrahedron)
— V(3.3.3.3) arccos (0) = ⁠π/2⁠ 90°
Rhombic dodecahedron
(Dual of cuboctahedron)
— V(3.4.3.4) arccos (-⁠1/2⁠) = ⁠2π/3⁠ 120°
Rhombic triacontahedron
(Dual of icosidodecahedron)
— V(3.5.3.5) arccos (-⁠√5+1/4⁠) = ⁠4π/5⁠ 144°
Medial rhombic triacontahedron
(Dual of dodecadodecahedron)
— V(5.⁠5/2⁠.5.⁠5/2⁠) arccos (-⁠1/2⁠) = ⁠2π/3⁠ 120°
Great rhombic triacontahedron
(Dual of great icosidodecahedron)
— V(3.⁠5/2⁠.3.⁠5/2⁠) arccos (⁠√5-1/4⁠) = ⁠2π/5⁠ 72°
Duals of the ditrigonal polyhedra
Small triambic icosahedron
(Dual of small ditrigonal icosidodecahedron)
— V(3.⁠5/2⁠.3.⁠5/2⁠.3.⁠5/2⁠)
Medial triambic icosahedron
(Dual of ditrigonal dodecadodecahedron)
— V(5.⁠5/3⁠.5.⁠5/3⁠.5.⁠5/3⁠)
Great triambic icosahedron
(Dual of great ditrigonal icosidodecahedron)
— V⁠(3.5.3.5.3.5)/2⁠
Duals of the hemipolyhedra
Tetrahemihexacron
(Dual of tetrahemihexahedron)
— V(3.4.⁠3/2⁠.4) π − ⁠π/2⁠ 90°
Hexahemioctacron
(Dual of cubohemioctahedron)
— V(4.6.⁠4/3⁠.6) π − ⁠π/3⁠ 120°
Octahemioctacron
(Dual of octahemioctahedron)
— V(3.6.⁠3/2⁠.6) π − ⁠π/3⁠ 120°
Small dodecahemidodecacron
(Dual of small dodecahemidodecacron)
— V(5.10.⁠5/4⁠.10) π − ⁠π/5⁠ 144°
Small icosihemidodecacron
(Dual of small icosihemidodecacron)
— V(3.10.⁠3/2⁠.10) π − ⁠π/5⁠ 144°
Great dodecahemicosacron
(Dual of great dodecahemicosahedron)
— V(5.6.⁠5/4⁠.6) π − ⁠π/3⁠ 120°
Small dodecahemicosacron
(Dual of small dodecahemicosahedron)
— V(⁠5/2⁠.6.⁠5/3⁠.6) π − ⁠π/3⁠ 120°
Great icosihemidodecacron
(Dual of great icosihemidodecacron)
— V(3.⁠10/3⁠.⁠3/2⁠.⁠10/3⁠) π − ⁠2π/5⁠ 72°
Great dodecahemidodecacron
(Dual of great dodecahemidodecacron)
— V(⁠5/2⁠.⁠10/3⁠.⁠5/3⁠.⁠10/3⁠) π − ⁠2π/5⁠ 72°

References

  • Coxeter, Regular Polytopes (1963), Macmillan Company
    • Regular Polytopes, (3rd edition, 1973), Dover edition, ISBN 0-486-61480-8 (Table I: Regular Polytopes, (i) The nine regular polyhedra {p,q} in ordinary space)
  • Williams, Robert (1979). The Geometrical Foundation of Natural Structure: A Source Book of Design. Dover Publications, Inc. ISBN 0-486-23729-X.  (Section 3-7 to 3-9)
  • Weisstein, Eric W.. "Uniform Polyhedron". http://mathworld.wolfram.com/UniformPolyhedron.html.