6-demicubic honeycomb explained

bgcolor=#e7dcc3 colspan=26-demicubic honeycomb
bgcolor=#ffffff align=center colspan=2(No image)
TypeUniform 6-honeycomb
FamilyAlternated hypercube honeycomb
Schläfli symbolh
h
ht0,6
Coxeter diagram =
=
Facets
Vertex figure
Coxeter group

{\tilde{B}}6

[4,3,3,3,3<sup>1,1</sup>]

{\tilde{D}}6

[3<sup>1,1</sup>,3,3,3<sup>1,1</sup>]
The 6-demicubic honeycomb or demihexeractic honeycomb is a uniform space-filling tessellation (or honeycomb) in Euclidean 6-space. It is constructed as an alternation of the regular 6-cube honeycomb.

It is composed of two different types of facets. The 6-cubes become alternated into 6-demicubes h and the alternated vertices create 6-orthoplex facets.

D6 lattice

The vertex arrangement of the 6-demicubic honeycomb is the D6 lattice.[1] The 60 vertices of the rectified 6-orthoplex vertex figure of the 6-demicubic honeycomb reflect the kissing number 60 of this lattice.[2] The best known is 72, from the E6 lattice and the 222 honeycomb.

The D lattice (also called D) can be constructed by the union of two D6 lattices. This packing is only a lattice for even dimensions. The kissing number is 25=32 (2n-1 for n<8, 240 for n=8, and 2n(n-1) for n>8).[3]

The D lattice (also called D and C) can be constructed by the union of all four 6-demicubic lattices:[4] It is also the 6-dimensional body centered cubic, the union of two 6-cube honeycombs in dual positions.

∪ ∪ ∪ = ∪ .

The kissing number of the D6* lattice is 12 (2n for n≥5).[5] and its Voronoi tessellation is a trirectified 6-cubic honeycomb,, containing all birectified 6-orthoplex Voronoi cell, .[6]

Symmetry constructions

There are three uniform construction symmetries of this tessellation. Each symmetry can be represented by arrangements of different colors on the 64 6-demicube facets around each vertex.

Coxeter groupSchläfli symbolCoxeter-Dynkin diagramVertex figure
Symmetry
Facets/verf

{\tilde{B}}6

= [3<sup>1,1</sup>,3,3,3,4]
= [1<sup>+</sup>,4,3,3,3,3,4]
h =
[3,3,3,4]
64: 6-demicube
12: 6-orthoplex

{\tilde{D}}6

= [3<sup>1,1</sup>,3,3<sup>1,1</sup>]
= [1<sup>+</sup>,4,3,3,3<sup>1,1</sup>]
h =
[3<sup>3,1,1</sup>]
32+32: 6-demicube
12: 6-orthoplex
½

{\tilde{C}}6

= (4,3,3,3,4,2+)
ht0,632+16+16: 6-demicube
12: 6-orthoplex

See also

External links

Notes and References

  1. Web site: The Lattice D6.
  2. Sphere packings, lattices, and groups, by John Horton Conway, Neil James Alexander Sloane, Eiichi Bannaihttps://books.google.com/books?id=upYwZ6cQumoC&amp;dq=Sphere%20Packings%2C%20Lattices%20and%20Groups&amp;pg=PR19
  3. Conway (1998), p. 119
  4. Web site: The Lattice D6.
  5. Conway (1998), p. 120
  6. Conway (1998), p. 466