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{| class="wikitable" align="right" style="margin-left:10px" width="360"
The writer is known as Wilber Pegues. For years she's been living in Kentucky but her spouse desires them to move. It's not a typical thing but what she likes doing is to play domino but she doesn't have the time lately. Credit authorising is how he makes money.<br><br>Stop by my website ... [http://bigpolis.com/blogs/post/6503 free psychic]
!bgcolor=#e7dcc3 colspan=2|Alternated cubic honeycomb
|-
|bgcolor=#ffffff align=center colspan=2|[[Image:Alternated cubic tiling.png|210px]]&nbsp;[[File:HC P1-P3.png|130px]]
|-
|bgcolor=#e7dcc3|Type||[[Convex uniform honeycomb|Uniform honeycomb]]
|-
|bgcolor=#e7dcc3|Family||[[Alternated hypercubic honeycomb]]
|-
|bgcolor=#e7dcc3|Indexing<ref>For cross-referencing, they are given with list indices from Andreini (1-22), Williams(1-2,9-19), Johnson (11-19, 21-25, 31-34, 41-49, 51-52, 61-65), and Grünbaum(1-28).</ref>
|J<sub>21,31,51</sub>, A<sub>2</sub><BR>W<sub>9</sub>, G<sub>1</sub>
|-
|bgcolor=#e7dcc3|[[Schläfli symbol]]||h{4,3,4}<BR>{3<sup>[4]</sup>}<BR>ht<sub>0,3</sub>{4,3,4}
|-
|bgcolor=#e7dcc3|[[Coxeter-Dynkin diagram]]s||{{CDD|nodes_10ru|split2|node|4|node}} or {{CDD|node_h1|4|node|3|node|4|node}}<BR>{{CDD|node_1|split1|nodes|split2|node}} or {{CDD|nodes|split2|node|4|node_h1}} or {{CDD|nodes_hh|4a4b|branch}}<BR>{{CDD|node_h|4|node|4|node|2|node_h|infin|node}}<BR>{{CDD|node_h|4|node|4|node_h|2|node_h|infin|node}}<BR>{{CDD|node_h|infin|node|2|node_h|infin|node|2|node_h|infin|node}}
 
|-
|bgcolor=#e7dcc3|Cell types||[[tetrahedron|{3,3}]], [[octahedron|{3,4}]]
|-
|bgcolor=#e7dcc3|Face types||[[triangle]] {3}
|-
|bgcolor=#e7dcc3|Edge figure||[{3,3}.{3,4}]<sup>2</sup><BR>([[rectangle]])
|-
|bgcolor=#e7dcc3|Vertex figure||[[Image:Alternated cubic honeycomb verf.svg|80px]][[File:Uniform t0 3333 honeycomb verf.png|80px]]<BR>[[File:Cuboctahedron.png|80px]][[File:Cantellated tetrahedron.png|80px]]<BR>([[cuboctahedron]])
|-
|bgcolor=#e7dcc3|Cells/edge||[{3,3}.{3,4}]<sup>2</sup>
|-
|bgcolor=#e7dcc3|Faces/edge||4 {3}
|-
|bgcolor=#e7dcc3|Cells/vertex||[[tetrahedron|{3,3}]]<sup>8</sup>+[[octahedron|{3,4}]]<sup>6</sup>
|-
|bgcolor=#e7dcc3|Faces/vertex||24 {3}
|-
|bgcolor=#e7dcc3|Edges/vertex||12
|-
|bgcolor=#e7dcc3|[[Space group|Symmetry group]]||Fm{{overline|3}}m (225)
|-
|bgcolor=#e7dcc3|[[Coxeter notation|Symmetry]]||½<math>{\tilde{C}}_3</math>, [1<sup>+</sup>,4,3,4]<BR><math>{\tilde{B}}_3</math>, [4,3<sup>1,1</sup>]<BR><math>{\tilde{A}}_3</math>×2, <[3<sup>[4]</sup>]>
|-
|bgcolor=#e7dcc3|Dual||Dodecahedrille<BR>[[rhombic dodecahedral honeycomb]]
|-
|bgcolor=#e7dcc3|Properties||[[vertex-transitive]], [[edge-transitive]], [[face-transitive]], [[quasiregular honeycomb]]
|}
 
The '''tetrahedral-octahedral  honeycomb''' or '''alternated cubic honeycomb''' or '''half cubic honeycomb''' is a space-filling [[tessellation]] (or [[honeycomb (geometry)|honeycomb]]) in [[Euclidean 3-space]].  It is composed of alternating [[octahedron|octahedra]] and [[tetrahedron|tetrahedra]] in a ratio of 1:2.
 
It is [[vertex-transitive]] with 8 [[tetrahedra]] and 6 [[octahedra]] around each [[Vertex (geometry)|vertex]]. It is [[edge-transitive]] with 2 tetrahedra and 2 octahedra alternating on each edge.
 
[[John Horton Conway]] calls this honeycomb a '''Tetroctahedrille''', and its dual [[Rhombic dodecahedral honeycomb|dodecahedrille]].
 
It is part of an infinite family of [[uniform tessellation]]s called [[alternated hypercubic honeycomb]]s, formed as an [[Alternation (geometry)|alternation]] of a hypercubic honeycomb and being composed of [[demihypercube]] and [[cross-polytope]] facets.
 
In this case of 3-space, the [[cubic honeycomb]] is alternated, reducing the cubic cells to tetrahedra, and the deleted vertices create octahedral voids. As such it can be represented by an extended [[Schläfli symbol]] h{4,3,4} as containing ''half'' the vertices of the {4,3,4} cubic honeycomb.
 
There's a similar honeycomb called [[gyrated tetrahedral-octahedral honeycomb]] which has layers rotated 60 degrees so half the edges have neighboring rather than alternating tetrahedra and octahedra.
 
==Cartesian coordinates==
 
For an ''alternted cubic honeycomb'', with edges parallel to the axes and with an edge length of 1, the [[Cartesian coordinates]] of the vertices are: (For all integral values: ''i'',''j'',''k'' with ''i''+''j''+''k'' [[even number|even]])
:(i, j, k)
 
== Images ==
{| class="wikitable" width=200
|align=center valign=top|[[Image:TetraOctaHoneycomb-VertexConfig.svg|180px]]<BR>This diagram shows an [[exploded view]] of the cells surrounding each vertex.
|}
 
== Symmetry==
There is two reflective construction and many alternated [[Cubic_honeycomb#Uniform_colorings|cubic honeycomb]] ones, examples:
{| class=wikitable
!Symmetry
!<math>{\tilde{B}}_3</math>, [4,3<sup>1,1</sup>]<BR>= ½<math>{\tilde{C}}_3</math>, [1<sup>+</sup>,4,3,4]
!<math>{\tilde{A}}_3</math>, [3<sup>[4]</sup>]<BR>= ½<math>{\tilde{B}}_3</math>, [1<sup>+</sup>,4,3<sup>1,1</sup>]
!<nowiki>[[</nowiki>(4,3,4,2<sup>+</sup>)]]
![(4,3,4,2<sup>+</sup>)]
|-
![[Space group]]
!Fm{{overline|3}}m (225)
!F{{overline|4}}3m (216)
!I{{overline|4}}3m (217)
!P{{overline|4}}3m (215)
|-
!Image
|[[Image:Tetrahedral-octahedral honeycomb.png|160px]]
|[[Image:Tetrahedral-octahedral honeycomb2.png|160px]]
|
|
|-
!Types of tetrahedra
!1
!2
!2
!4
|-
![[Coxeter diagram|Coxeter<BR>diagram]]
!{{CDD|nodes_10ru|split2|node|4|node}} = {{CDD|node_h1|4|node|3|node|4|node}}
! {{CDD|node_1|split1|nodes|split2|node}} = {{CDD|nodes|split2|node|4|node_h1}} = {{CDD|node_h0|4|node|3|node|4|node_h1}}
!{{CDD|branch|4a4b|nodes_hh}}
!{{CDD|node_h|4|node|3|node|4|node_h}}
|}
 
=== Projection by folding ===
 
The ''alternated cubic honeycomb'' can be orthogonally projected into the planar [[square tiling]] by a [[Coxeter–Dynkin diagram#Geometric folding|geometric folding]] operation that maps one pairs of mirrors into each other. The projection of the ''alternated cubic honeycomb'' creates two offset copies of the square tiling [[vertex arrangement]] of the plane:
 
{|class=wikitable
![[Coxeter group|Coxeter<BR>group]]
![[Coxeter–Dynkin diagram#Geometric folding|Coxeter<BR>diagram]]
!Graph
|- align=center
!<math>{\tilde{A}}_3</math>
|{{CDD|node_1|split1|nodes|split2|node}}
|[[File:Tiling Dual Semiregular V4-8-8 Tetrakis Square.svg|100px]]<BR>alternated cubic honeycomb
|- align=center
!<math>{\tilde{C}}_2</math>
|{{CDD|node_1|4|node|4|node}}
|[[File:Uniform tiling 44-t0.png|100px]]<BR>[[square tiling]]
|}
 
==A3/D3 lattice==
Its [[vertex arrangement]] represents an [[A3 lattice|A<sub>3</sub> lattice]] or ''D<sub>3</sub> lattice''.<ref>http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/D3.html</ref><ref>http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/A3.html</ref> It is the 3-dimensional case of a [[simplectic honeycomb]]. Its Voronoi cell is a [[rhombic dodecahedron]], the dual of the [[cuboctahedron]] vertex figure for the tet-oct honeycomb.
 
The D{{sup sub|+|3}} packing can be constructed by the union of two D<sub>3</sub> (or A<sub>3</sub>) lattices. The D{{sup sub|+|n}} packing is only a lattice for even dimensions. The kissing number is 2<sup>2</sup>=4, (2<sup>n-1</sup> for n<8, 240 for n=8, and 2n(n-1) for n>8).<ref>Conway (1998), p. 119</ref>
:{{CDD|node_1|split1|nodes|split2|node}} + {{CDD|node|split1|nodes|split2|node_1}}
 
The A{{sup sub|*|3}} or D{{sup sub|*|3}} lattice (also called A{{sup sub|4|3}} or D{{sup sub|4|3}}) can be constructed by the union of all four A<sub>3</sub> lattices, and is identical to the [[vertex arrangement]] of the [[disphenoid tetrahedral honeycomb]], dual honeycomb of the uniform [[bitruncated cubic honeycomb]]:<ref>http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/Ds3.html</ref>  It is also the [[body centered cubic]], the union of two [[cubic honeycomb]]s in dual positions.
:{{CDD|node_1|split1|nodes|split2|node}} + {{CDD|node|split1|nodes_10luru|split2|node}} + {{CDD|node|split1|nodes_01lr|split2|node}} + {{CDD|node|split1|nodes|split2|node_1}} = dual of {{CDD|node_1|split1|nodes_11|split2|node_1}} = {{CDD|node_1|4|node|3|node|4|node}} + {{CDD|node|4|node|3|node|4|node_1}}.
 
The [[kissing number]] of the D{{sup sub|*|3}} lattice is 8<ref>Conway (1998), p. 120</ref> and its [[Voronoi tessellation]] is a [[bitruncated cubic honeycomb]], {{CDD|branch_11|4a4b|nodes}}, containing all [[truncated octahedron|truncated octahedral]] [[Voronoi cell]]s, {{CDD|node|4|node_1|3|node_1}}.<ref>Conway (1998), p. 466</ref>
 
== Related honeycombs==
The [4,3,4], {{CDD|node|4|node|3|node|4|node}}, [[Coxeter group]] generates 15 permutations of uniform tessellations, 9 with distinct geometry including the alternated cubic honeycomb. The [[Expansion (geometry)|expanded]] cubic honeycomb (also known as the runcinated tesseractic honeycomb) is geometrically identical to the cubic honeycomb.
{{C3 honeycombs}}
 
The [4,3<sup>1,1</sup>], {{CDD|node|4|node|split1|nodes}}, [[Coxeter group]] generates 9 permutations of uniform tessellations, 4 with distinct geometry including the alternated cubic honeycomb.
{{B3 honeycombs}}
 
This honeycomb is one of [[Uniform polyteron#Regular and uniform honeycombs|five distinct uniform honeycombs]]<ref>[http://mathworld.wolfram.com/Necklace.html], [http://oeis.org/A000029 A000029] 6-1 cases, skipping one with zero marks</ref> constructed by the <math>{\tilde{A}}_3</math> [[Coxeter group]]. The symmetry can be multiplied by the symmetry of rings in the [[Coxeter–Dynkin diagram]]s:
{{A3 honeycombs}}
 
==See also==
* [[Architectonic and catoptric tessellation]]
*[[Cubic honeycomb]]
*[[Space frame]]
 
==Notes==
{{reflist}}
 
== References ==
* [[John Horton Conway|John H. Conway]], Heidi Burgiel, Chaim Goodman-Strauss, (2008) ''The Symmetries of Things'', ISBN 978-1-56881-220-5 (Chapter 21, Naming the Archimedean and Catalan polyhedra and tilings, Architectonic and Catoptric tessellations, p 292-298, includes all the nonprismatic forms)
* [[George Olshevsky]], ''Uniform Panoploid Tetracombs'', Manuscript (2006) ''(Complete list of 11 convex uniform tilings, 28 convex uniform honeycombs, and 143 convex uniform tetracombs)''
* [[Branko Grünbaum]], Uniform tilings of 3-space. [[Geombinatorics]] 4(1994), 49 - 56.
* [[Norman Johnson (mathematician)|Norman Johnson]] ''Uniform Polytopes'', Manuscript (1991)
* {{The Geometrical Foundation of Natural Structure (book)}}
* {{cite book | first=Keith | last=Critchlow | authorlink=Keith Critchlow  | title=Order in Space: A design source book | publisher=Viking Press| year=1970 | isbn=0-500-34033-1 }}
* '''Kaleidoscopes: Selected Writings of H.S.M. Coxeter''', edited by F. Arthur Sherk, Peter McMullen, Anthony C. Thompson, Asia Ivic Weiss, Wiley-Interscience Publication, 1995, ISBN 978-0-471-01003-6 [http://www.wiley.com/WileyCDA/WileyTitle/productCd-0471010030.html]
** (Paper 22) H.S.M. Coxeter, ''Regular and Semi Regular Polytopes I'', [Math. Zeit. 46 (1940) 380-407, MR 2,10] (1.9 Uniform space-fillings)
** (Paper 24) H.S.M. Coxeter, ''Regular and Semi-Regular Polytopes III'', [Math. Zeit. 200 (1988) 3-45]
* [[Alfredo Andreini|A. Andreini]], ''Sulle reti di poliedri regolari e semiregolari e sulle corrispondenti reti correlative'' (On the regular and semiregular nets of polyhedra and on the corresponding correlative nets), Mem. Società Italiana della Scienze, Ser.3, 14 (1905) 75–129.
* [[Duncan MacLaren Young Sommerville|D. M. Y. Sommerville]], ''An Introduction to the Geometry of '''n''' Dimensions.'' New York, E. P. Dutton, 1930. 196 pp. (Dover Publications edition, 1958) Chapter X: The Regular Polytopes
* {{cite book |author=Conway JH, Sloane NJH |year=1998 |title=Sphere Packings, Lattices and Groups |edition=3rd |isbn=0-387-98585-9}}
 
== External links ==
{{Commons category|Tetrahedral-octahedral honeycomb}}
*[http://www.wtcsitememorial.com/ent/entI=706963.html Architectural design made with Tetrahedrons and regular Pyramids based square.(2003) ]
* {{KlitzingPolytopes|flat.htm|3D Euclidean Honeycombs|x3o3o *b4o - octet  - O21}}
* [http://www.doskey.com/polyhedra/UniformHoneycombs.html Uniform Honeycombs in 3-Space: 11-Octet]
 
{{Honeycombs}}
 
[[Category:Honeycombs (geometry)]]
[[Category:Polychora]]

Latest revision as of 09:32, 11 January 2015

The writer is known as Wilber Pegues. For years she's been living in Kentucky but her spouse desires them to move. It's not a typical thing but what she likes doing is to play domino but she doesn't have the time lately. Credit authorising is how he makes money.

Stop by my website ... free psychic