List of isotoxal polyhedra and tilings

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In geometry, isotoxal polyhedra and tilings are defined by the property that they have symmetries taking any edge to any other edge. [1] Polyhedra with this property can also be called "edge-transitive", but they should be distinguished from edge-transitive graphs, where the symmetries are combinatorial rather than geometric.

Contents

Regular polyhedra are isohedral (face-transitive), isogonal (vertex-transitive), and isotoxal (edge-transitive).

Quasiregular polyhedra are isogonal and isotoxal, but not isohedral; their duals are isohedral and isotoxal, but not isogonal.

The dual of an isotoxal polyhedron is also an isotoxal polyhedron. (See the Dual polyhedron article.)

Convex isotoxal polyhedra

The dual of a convex polyhedron is also a convex polyhedron. [2]

There are nine convex isotoxal polyhedra based on the Platonic solids: the five (regular) Platonic solids, the two (quasiregular) common cores of dual Platonic solids, and their two duals.

The vertex figures of the quasiregular forms are (squares or) rectangles; the vertex figures of the duals of the quasiregular forms are (equilateral triangles and equilateral triangles, or) equilateral triangles and squares, or equilateral triangles and regular pentagons.

FormRegularDual regularQuasiregularQuasiregular dual
Wythoff symbol q | 2 pp | 2 q2 | p q 
Vertex configuration pqqpp.q.p.q
p=3
q=3
Uniform polyhedron-33-t0.svg
Tetrahedron
{3,3}
CDel node 1.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node.png
3 | 2 3
Uniform polyhedron-33-t2.svg
Tetrahedron
{3,3}
CDel node.pngCDel 3.pngCDel node.pngCDel 3.pngCDel node 1.png
3 | 2 3
Uniform polyhedron-33-t1.svg
Tetratetrahedron
(Octahedron)
CDel node.pngCDel 3.pngCDel node 1.pngCDel 3.pngCDel node.png
2 | 3 3
Hexahedron.svg
Cube
(Rhombic hexahedron)
p=4
q=3
Uniform polyhedron-43-t0.svg
Cube
{4,3}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node.png
3 | 2 4
Uniform polyhedron-43-t2.svg
Octahedron
{3,4}
CDel node.pngCDel 4.pngCDel node.pngCDel 3.pngCDel node 1.png
4 | 2 3
Uniform polyhedron-43-t1.svg
Cuboctahedron
CDel node.pngCDel 4.pngCDel node 1.pngCDel 3.pngCDel node.png
2 | 3 4
Rhombicdodecahedron.jpg
Rhombic dodecahedron
p=5
q=3
Uniform polyhedron-53-t0.svg
Dodecahedron
{5,3}
CDel node 1.pngCDel 5.pngCDel node.pngCDel 3.pngCDel node.png
3 | 2 5
Uniform polyhedron-53-t2.svg
Icosahedron
{3,5}
CDel node.pngCDel 5.pngCDel node.pngCDel 3.pngCDel node 1.png
5 | 2 3
Uniform polyhedron-53-t1.svg
Icosidodecahedron
CDel node.pngCDel 5.pngCDel node 1.pngCDel 3.pngCDel node.png
2 | 3 5
Rhombictriacontahedron.svg
Rhombic triacontahedron

Isotoxal star-polyhedra

The dual of a non-convex polyhedron is also a non-convex polyhedron. [2] (By contraposition.)

There are ten non-convex isotoxal polyhedra based on the quasiregular octahedron, cuboctahedron, and icosidodecahedron: the five (quasiregular) hemipolyhedra based on the quasiregular octahedron, cuboctahedron, and icosidodecahedron, and their five (infinite) duals:

FormQuasiregularQuasiregular dual
p=3
q=3
Tetrahemihexahedron.png Tetrahemihexahedron vertfig.png
Tetrahemihexahedron
Tetrahemihexacron.png
Tetrahemihexacron
p=4
q=3
Cubohemioctahedron.png Cubohemioctahedron vertfig.png
Cubohemioctahedron
Hexahemioctacron.png
Hexahemioctacron
Octahemioctahedron.png Octahemioctahedron vertfig.png
Octahemioctahedron
Hexahemioctacron.png
Octahemioctacron (visually indistinct from Hexahemioctacron) (*)
p=5
q=3
Small icosihemidodecahedron.png Small icosihemidodecahedron vertfig.png
Small icosihemidodecahedron
Small dodecahemidodecacron.png
Small icosihemidodecacron (visually indistinct from Small dodecahemidodecacron) (*)
Small dodecahemidodecahedron.png Small dodecahemidodecahedron vertfig.png
Small dodecahemidodecahedron
Small dodecahemidodecacron.png
Small dodecahemidodecacron

(*) Faces, edges, and intersection points are the same; only, some other of these intersection points, not at infinity, are considered as vertices.

There are sixteen non-convex isotoxal polyhedra based on the Kepler–Poinsot polyhedra: the four (regular) Kepler–Poinsot polyhedra, the six (quasiregular) common cores of dual Kepler–Poinsot polyhedra (including four hemipolyhedra), and their six duals (including four (infinite) hemipolyhedron-duals):

FormRegularDual regularQuasiregularQuasiregular dual
Wythoff symbol q | 2 pp | 2 q2 | p q 
Vertex configuration pqqpp.q.p.q
p=5/2
q=3
Great stellated dodecahedron.png Great stellated dodecahedron vertfig.png
Great stellated dodecahedron
{5/2,3}

CDel node 1.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node.pngCDel 3.pngCDel node.png
3 | 2 5/2

Great icosahedron.png Great icosahedron vertfig.svg
Great icosahedron
{3,5/2}

CDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node.pngCDel 3.pngCDel node 1.png
5/2 | 2 3

Great icosidodecahedron.png Great icosidodecahedron vertfig.png
Great icosidodecahedron
 
CDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node 1.pngCDel 3.pngCDel node.png
2 | 3 5/2
DU54 great rhombic triacontahedron.png
Great rhombic triacontahedron
Great icosihemidodecahedron.png Great icosihemidodecahedron vertfig.png
Great icosihemidodecahedron
Great dodecahemidodecacron.png
Great icosihemidodecacron
Great dodecahemidodecahedron.png Great dodecahemidodecahedron vertfig.png
Great dodecahemidodecahedron
Great dodecahemidodecacron.png
Great dodecahemidodecacron
p=5/2
q=5
Small stellated dodecahedron.png Small stellated dodecahedron vertfig.png
Small stellated dodecahedron
{5/2,5}

CDel node 1.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node.pngCDel 5.pngCDel node.png
5 | 2 5/2

Great dodecahedron.png Great dodecahedron vertfig.png
Great dodecahedron
{5,5/2}

CDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node.pngCDel 5.pngCDel node 1.png
5/2 | 2 5

Dodecadodecahedron.png Dodecadodecahedron vertfig.png
Dodecadodecahedron
 
CDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node 1.pngCDel 5.pngCDel node.png
2 | 5 5/2
DU36 medial rhombic triacontahedron.png
Medial rhombic triacontahedron
Small dodecahemicosahedron.png Small dodecahemicosahedron vertfig.png
Small icosihemidodecahedron
Small dodecahemicosacron.png
Small dodecahemicosacron
Great dodecahemicosahedron.png Great dodecahemicosahedron vertfig.png
Great dodecahemidodecahedron
Small dodecahemicosacron.png
Great dodecahemicosacron

Finally, there are six other non-convex isotoxal polyhedra: the three quasiregular ditrigonal (3 | p q) star polyhedra, and their three duals:

QuasiregularQuasiregular dual
3 | p q 
Great ditrigonal icosidodecahedron.png Great ditrigonal icosidodecahedron vertfig.png
Great ditrigonal icosidodecahedron
3/2 | 3 5
CDel 3.pngCDel node.pngCDel d3.pngCDel rat.pngCDel d2.pngCDel node.pngCDel 5.pngCDel node 1.pngCDel 3.png
DU47 great triambic icosahedron.png
Great triambic icosahedron
Ditrigonal dodecadodecahedron.png Ditrigonal dodecadodecahedron vertfig.svg
Ditrigonal dodecadodecahedron
3 | 5/3 5
CDel 3.pngCDel node.pngCDel 5.pngCDel rat.pngCDel d3.pngCDel node 1.pngCDel 5.pngCDel node.pngCDel 3.png
DU41 medial triambic icosahedron.png
Medial triambic icosahedron
Small ditrigonal icosidodecahedron.png Small ditrigonal icosidodecahedron vertfig.svg
Small ditrigonal icosidodecahedron
3 | 5/2 3
CDel 3.pngCDel node.pngCDel 5.pngCDel rat.pngCDel d2.pngCDel node 1.pngCDel 3.pngCDel node.pngCDel 3.png
DU30 small triambic icosahedron.png
Small triambic icosahedron

Isotoxal tilings of the Euclidean plane

There are at least 5 polygonal tilings of the Euclidean plane that are isotoxal. (The self-dual square tiling recreates itself in all four forms.)

RegularDual regularQuasiregularQuasiregular dual
Uniform tiling 63-t0.svg
Hexagonal tiling
{6,3}
CDel node.pngCDel 6.pngCDel node.pngCDel 3.pngCDel node 1.png
6 | 2 3
Uniform tiling 63-t2.svg
Triangular tiling
{3,6}
CDel node 1.pngCDel 6.pngCDel node.pngCDel 3.pngCDel node.pngCDel 3.png
3 | 2 3
Uniform tiling 63-t1.svg
Trihexagonal tiling
CDel node.pngCDel 6.pngCDel node 1.pngCDel 3.pngCDel node.png
2 | 3 6
Star rhombic lattice.png
Rhombille tiling
Uniform tiling 44-t0.svg
Square tiling
{4,4}
CDel node.pngCDel 4.pngCDel node.pngCDel 4.pngCDel node 1.png
4 | 2 4
Uniform tiling 44-t2.svg
Square tiling
{4,4}
CDel node 1.pngCDel 4.pngCDel node.pngCDel 4.pngCDel node.png
2 | 4 4
Uniform tiling 44-t1.svg
Square tiling
{4,4}
CDel node.pngCDel 4.pngCDel node 1.pngCDel 4.pngCDel node.png
4 | 2 4
Uniform tiling 44-t0.svg
Square tiling
{4,4}

Isotoxal tilings of the hyperbolic plane

There are infinitely many isotoxal polygonal tilings of the hyperbolic plane, including the Wythoff constructions from the regular hyperbolic tilings {p,q}, and non-right (p q r) groups.

Here are six (p q 2) families, each with two regular forms, and one quasiregular form. All have rhombic duals of the quasiregular form, but only one is shown:

[p,q]{p,q}{q,p}r{p,q}Dual r{p,q}
Coxeter-Dynkin CDel node 1.pngCDel p.pngCDel node.pngCDel q.pngCDel node.pngCDel node.pngCDel p.pngCDel node.pngCDel q.pngCDel node 1.pngCDel node.pngCDel p.pngCDel node 1.pngCDel q.pngCDel node.pngCDel node.pngCDel p.pngCDel node f1.pngCDel q.pngCDel node.png
[7,3] Heptagonal tiling.svg
{7,3}
Order-7 triangular tiling.svg
{3,7}
Triheptagonal tiling.svg
r{7,3}
7-3 rhombille tiling.svg
[8,3] H2-8-3-dual.svg
{8,3}
H2-8-3-primal.svg
{3,8}
H2-8-3-rectified.svg
r{8,3}
H2-8-3-rhombic.svg
[5,4] H2-5-4-dual.svg
{5,4}
H2-5-4-primal.svg
{4,5}
H2-5-4-rectified.svg
r{5,4}
H2-5-4-rhombic.svg
[6,4] Uniform tiling 64-t0.png
{6,4}
Uniform tiling 64-t2.png
{4,6}
Uniform tiling 64-t1.png
r{6,4}
H2chess 246a.png
[8,4] Uniform tiling 84-t0.png
{8,4}
Uniform tiling 84-t2.png
{4,8}
Uniform tiling 84-t1.png
r{8,3}
H2chess 248a.png
[5,5] Uniform tiling 552-t0.png
{5,5}
Uniform tiling 552-t2.png
{5,5}
Uniform tiling 552-t1.png
r{5,5}
H2-5-4-primal.svg

Here's 3 example (p q r) families, each with 3 quasiregular forms. The duals are not shown, but have isotoxal hexagonal and octagonal faces.

Coxeter-Dynkin CDel 3.pngCDel node 1.pngCDel p.pngCDel node.pngCDel q.pngCDel node.pngCDel r.pngCDel 3.pngCDel node.pngCDel p.pngCDel node 1.pngCDel q.pngCDel node.pngCDel r.pngCDel 3.pngCDel node.pngCDel p.pngCDel node.pngCDel q.pngCDel node 1.pngCDel r.png
(4 3 3) Uniform tiling 433-t0.png
3 | 4 3
Uniform tiling 433-t1.png
3 | 4 3
Uniform tiling 433-t2.png
4 | 3 3
(4 4 3) Uniform tiling 443-t0.png
4 | 4 3
Uniform tiling 443-t1.png
3 | 4 4
Uniform tiling 443-t2.png
4 | 4 3
(4 4 4) Uniform tiling 444-t0.png
4 | 4 4
Uniform tiling 444-t1.png
4 | 4 4
Uniform tiling 444-t2.png
4 | 4 4

Isotoxal tilings of the sphere

All isotoxal polyhedra listed above can be made as isotoxal tilings of the sphere.

In addition as spherical tilings, there are two other families which are degenerate as polyhedra. Even ordered hosohedron can be semiregular, alternating two lunes, and thus isotoxal:

References

  1. Peter R. Cromwell, Polyhedra , Cambridge University Press 1997, ISBN   0-521-55432-2, p. 371
  2. 1 2 "duality". maths.ac-noumea.nc. Retrieved 2020-10-01.