Truncated trihexagonal tiling

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Truncated trihexagonal tiling
Truncated trihexagonal tiling
Type Semiregular tiling
Vertex configuration
4.6.12
Schläfli symbol tr{6,3} or
Wythoff symbol 2 6 3 |
Coxeter diagram
Symmetry p6m, [6,3], (*632)
Rotation symmetry p6, [6,3]+, (632)
Bowers acronym Othat
Dual Kisrhombille tiling
Properties Vertex-transitive

In geometry, the truncated trihexagonal tiling is one of eight semiregular tilings of the Euclidean plane. There are one square, one hexagon, and one dodecagon on each vertex. It has Schläfli symbol of tr{3,6}.

An equilateral variation with rhombi instead of squares, and isotoxal hexagons instead of regular

Names

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The name truncated trihexagonal tiling is analogous to truncated cuboctahedron and truncated icosidodecahedron, and misleading in the same way. An actual truncation of the trihexagonal tiling has rectangles instead of squares, and its hexagonal and dodecagonal faces can not both be regular.

Alternate interchangeable names are:

  • Great rhombitrihexagonal tiling
  • Rhombitruncated trihexagonal tiling
  • Omnitruncated hexagonal tiling, omnitruncated triangular tiling
  • Conway calls it a truncated hexadeltille.[1]
Trihexagonal tiling and its truncation

Uniform colorings

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There is only one uniform coloring of a truncated trihexagonal tiling, with faces colored by polygon sides. A 2-uniform coloring has two colors of hexagons. 3-uniform colorings can have 3 colors of dodecagons or 3 colors of squares.

1-uniform 2-uniform 3-uniform
Coloring        
Symmetry p6m, [6,3], (*632) p3m1, [3[3]], (*333)
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The truncated trihexagonal tiling has three related 2-uniform tilings, one being a 2-uniform coloring of the semiregular rhombitrihexagonal tiling. The first dissects the hexagons into 6 triangles. The other two dissect the dodecagons into a central hexagon and surrounding triangles and square, in two different orientations.[2][3]

Semiregular Dissections Semiregular 2-uniform 3-uniform
    
  
       
Dual Insets
           

Circle packing

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The Truncated trihexagonal tiling can be used as a circle packing, placing equal diameter circles at the center of every point. Every circle is in contact with 3 other circles in the packing (kissing number).[4]

 

Kisrhombille tiling

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Kisrhombille tiling
 
TypeDual semiregular tiling
Faces30-60-90 triangle
Coxeter diagram     
Symmetry groupp6m, [6,3], (*632)
Rotation groupp6, [6,3]+, (632)
Dual polyhedrontruncated trihexagonal tiling
Face configurationV4.6.12 
Propertiesface-transitive

The kisrhombille tiling or 3-6 kisrhombille tiling is a tiling of the Euclidean plane. It is constructed by congruent 30-60-90 triangles with 4, 6, and 12 triangles meeting at each vertex.

Subdividing the faces of these tilings creates the kisrhombille tiling. (Compare the disdyakis hexa-, dodeca- and triacontahedron, three Catalan solids similar to this tiling.)

The kisrhombille tiling under its dual (left) and under the floret pentagonal tiling (right), from which it can be created as a partial truncation.

Construction from rhombille tiling

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Conway calls it a kisrhombille[1] for his kis vertex bisector operation applied to the rhombille tiling. More specifically it can be called a 3-6 kisrhombille, to distinguish it from other similar hyperbolic tilings, like 3-7 kisrhombille.

It can be seen as an equilateral hexagonal tiling with each hexagon divided into 12 triangles from the center point. (Alternately it can be seen as a bisected triangular tiling divided into 6 triangles, or as an infinite arrangement of lines in six parallel families.)

It is labeled V4.6.12 because each right triangle face has three types of vertices: one with 4 triangles, one with 6 triangles, and one with 12 triangles.

Symmetry

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The kisrhombille tiling triangles represent the fundamental domains of p6m, [6,3] (*632 orbifold notation) wallpaper group symmetry. There are a number of small index subgroups constructed from [6,3] by mirror removal and alternation. [1+,6,3] creates *333 symmetry, shown as red mirror lines. [6,3+] creates 3*3 symmetry. [6,3]+ is the rotational subgroup. The commutator subgroup is [1+,6,3+], which is 333 symmetry. A larger index 6 subgroup constructed as [6,3*], also becomes (*333), shown in blue mirror lines, and which has its own 333 rotational symmetry, index 12.

Small index subgroups [6,3] (*632)
Index 1 2 3 6
Diagram            
Intl (orb.)
Coxeter
p6m (*632)
[6,3] =       =     
p3m1 (*333)
[1+,6,3] =       =    
p31m (3*3)
[6,3+] =      
cmm (2*22) pmm (*2222) p3m1 (*333)
[6,3*] =       =    
Direct subgroups
Index 2 4 6 12
Diagram          
Intl (orb.)
Coxeter
p6 (632)
[6,3]+ =       =     
p3 (333)
[1+,6,3+] =       =    
p2 (2222) p2 (2222) p3 (333)
[1+,6,3*] =       =    
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There are eight uniform tilings that can be based from the regular hexagonal tiling (or the dual triangular tiling). Drawing the tiles colored as red on the original faces, yellow at the original vertices, and blue along the original edges, there are 8 forms, 7 which are topologically distinct. (The truncated triangular tiling is topologically identical to the hexagonal tiling.)

Uniform hexagonal/triangular tilings
Symmetry: [6,3], (*632) [6,3]+
(632)
[6,3+]
(3*3)
{6,3} t{6,3} r{6,3} t{3,6} {3,6} rr{6,3} tr{6,3} sr{6,3} s{3,6}
                                                     
                 
63 3.122 (3.6)2 6.6.6 36 3.4.6.4 4.6.12 3.3.3.3.6 3.3.3.3.3.3
Uniform duals
                 
V63 V3.122 V(3.6)2 V63 V36 V3.4.6.4 V.4.6.12 V34.6 V36

Symmetry mutations

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This tiling can be considered a member of a sequence of uniform patterns with vertex figure (4.6.2p) and Coxeter-Dynkin diagram      . For p < 6, the members of the sequence are omnitruncated polyhedra (zonohedra), shown below as spherical tilings. For p > 6, they are tilings of the hyperbolic plane, starting with the truncated triheptagonal tiling.

*n32 symmetry mutation of omnitruncated tilings: 4.6.2n
Sym.
*n32
[n,3]
Spherical Euclid. Compact hyperb. Paraco. Noncompact hyperbolic
*232
[2,3]
*332
[3,3]
*432
[4,3]
*532
[5,3]
*632
[6,3]
*732
[7,3]
*832
[8,3]
*∞32
[∞,3]
 
[12i,3]
 
[9i,3]
 
[6i,3]
 
[3i,3]
Figures                        
Config. 4.6.4 4.6.6 4.6.8 4.6.10 4.6.12 4.6.14 4.6.16 4.6.∞ 4.6.24i 4.6.18i 4.6.12i 4.6.6i
Duals                        
Config. V4.6.4 V4.6.6 V4.6.8 V4.6.10 V4.6.12 V4.6.14 V4.6.16 V4.6.∞ V4.6.24i V4.6.18i V4.6.12i V4.6.6i

See also

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Notes

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  1. ^ a b Conway, 2008, Chapter 21, Naming Archimedean and Catalan polyhedra and tilings, p288 table
  2. ^ Chavey, D. (1989). "Tilings by Regular Polygons—II: A Catalog of Tilings". Computers & Mathematics with Applications. 17: 147–165. doi:10.1016/0898-1221(89)90156-9.
  3. ^ "Uniform Tilings". Archived from the original on 2006-09-09. Retrieved 2006-09-09.
  4. ^ Order in Space: A design source book, Keith Critchlow, p.74-75, pattern D

References

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  • Williams, Robert (1979). The Geometrical Foundation of Natural Structure: A Source Book of Design. Dover Publications, Inc. p. 41. ISBN 0-486-23729-X.
  • John H. Conway, Heidi Burgiel, Chaim Goodman-Strauss, The Symmetries of Things 2008, ISBN 978-1-56881-220-5 [1]
  • Keith Critchlow, Order in Space: A design source book, 1970, p. 69-61, Pattern G, Dual p. 77-76, pattern 4
  • Dale Seymour and Jill Britton, Introduction to Tessellations, 1989, ISBN 978-0866514613, pp. 50–56
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