Operations on maps 2 - Babeș-Bolyai Universitychem.ubbcluj.ro/~diudea/cursuri si referate...1...
Transcript of Operations on maps 2 - Babeș-Bolyai Universitychem.ubbcluj.ro/~diudea/cursuri si referate...1...
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Operations on MapsOperations on Maps
MirceaMircea V. DiudeaV. Diudea
Faculty of Chemistry and Chemical EngineeringFaculty of Chemistry and Chemical EngineeringBabesBabes--BolyaiBolyai UniversityUniversity400028400028 ClujCluj, ROMANIA, ROMANIA
[email protected]@chem.ubbcluj.ro
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ContentsContents
Cage Building by Map OperationsCage Building by Map Operations1.1. Capra, Ca/SCapra, Ca/S112.2. Septupling SSeptupling S22
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Operations on MapsOperations on Maps
•• A A map map M M is a combinatorial representation of a closed is a combinatorial representation of a closed surface.surface.11
•• Several operations on a map allow its transformation Several operations on a map allow its transformation into new maps (into new maps (convex polyhedraconvex polyhedra).).
•• PlatonicPlatonic polyhedra:polyhedra: Tetrahedron, Cube, Octahedron,Tetrahedron, Cube, Octahedron,Dodecahedron and IcosahedronDodecahedron and Icosahedron
1. Pisanski, T.; Randić, M. Bridges between Geometry and Graph Theory. In: Geometry at Work, M. A. A. Notes, 2000, 53, 174-194.
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EulerEuler Theorem on PolyhedraTheorem on Polyhedra
v v –– e + fe + f = = χχ = = 22((11 –– gg))
χχ = = EulerEuler’’s s characteristiccharacteristicv = v = number of vertices, number of vertices, e = e = number of edges,number of edges,f = f = number of faces,number of faces,gg = genus ; = genus ; ((gg = 0 for a sphere; 1 for a = 0 for a sphere; 1 for a torustorus))..
Any map Any map MM and its transforms by map operations will obey the and its transforms by map operations will obey the EulerEuler theoremtheorem11
1. L. Euler, Elementa doctrinae solidorum, Novi Comment. Acad. Sci. I. PetropolitanaeComment. Acad. Sci. I. Petropolitanae1758, 4, 109-140.
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Platonic SolidsPlatonic Solids
OctahedronOctahedronCubeCubeTetrahedronTetrahedron
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Platonic SolidsPlatonic Solids
IcosahedronIcosahedronDodecahedronDodecahedron
Dual of a triangulation is always a cubic net.Dual of a triangulation is always a cubic net.
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Schlegel Schlegel projectionprojection
•• A projection of a sphereA projection of a sphere--like polyhedron like polyhedron on a plane is called aon a plane is called a SchlegelSchlegel diagram.diagram.
•• In a polyhedron, theIn a polyhedron, the centercenter of diagramof diagram is is taken either a taken either a vertexvertex, the , the center of ancenter of anedgeedge or the or the center of a facecenter of a face
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Cube Cube and its dualand its dual,, OctahedronOctahedron
CubeCube
OctahedronOctahedron
Du
Du
SchlegelSchlegel diagramsdiagrams
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PolygonalPolygonal PPss CappingCapping
•• CappingCapping PPss (s = 3, 4, 5) of a face is achieved as follows:(s = 3, 4, 5) of a face is achieved as follows:11•• Add a Add a new vertex in the centernew vertex in the center of the of the faceface. Put . Put s s --33 points on the points on the
boundary edgesboundary edges. . •• Connect the central point with one vertex (the end points includConnect the central point with one vertex (the end points included) ed)
on each edge. on each edge. •• The parent face is thus covered by: The parent face is thus covered by: trigonstrigons ((ss = 3), = 3),
tetragonstetragons ((ss = 4) = 4) pentagonspentagons ((ss = 5). = 5).
•• The The PP33 operation is also called operation is also called stellationstellation oror(centered) (centered) triangulationtriangulation. .
•• When all the faces of a map are thus operated, it is referred toWhen all the faces of a map are thus operated, it is referred to as as an omnicapping an omnicapping PPss operation. operation.
1. M. V. Diudea, Covering forms in nanostructures, Forma 2004 (submitted)
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The resulting map shows the relations:The resulting map shows the relations:
PPss ((M M ):):;;
Maps transformed as above form Maps transformed as above form dual pairs dual pairs ::
Vertex Vertex multiplication multiplication ratio by this ratio by this dualizationdualization is always: is always:
Since:Since:
PolygonalPolygonal PPss CappingCapping
000 )3( fesvv +−+=0ese =
00 fsf =
)())(( 3 MLeMPDu =
))(())(( 4 MMeMeMPDu =
)())(( 5 MSnMPDu =
00/)( dvDuv =
0000))(()( vdfsMPfDuv s ===
0000 )2( seesfse =−+=
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PP33((DodecahedronDodecahedron))PP33((CubeCube))
PP3 3 Capping = TriangulationCapping = Triangulation
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PP44((DodecahedronDodecahedron))11PP44((CubeCube))11
PP4 4 Capping = TetrangulationCapping = Tetrangulation
1. Catalan objects (i.e., duals of the Archimedean solids).2. B. de La Vaissière, P. W. Fowler, and M. Deza, J. Chem. Inf. Comput. Sci.,
2001, 41, 376-386.
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PP55((DodecahedronDodecahedron))PP55((CubeCube))
PP5 5 Capping = PentangulationCapping = Pentangulation11
1. For other operation names see www.georgehart.com\virtual-polyhedra\conway_notation.html
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7.7. Capra Capra 11 Ca Ca ((M M )) / Septupling/ Septupling
•• GoldbergGoldberg22 relation:relation:mm = (= (a a 22 + + abab + + b b 22); ); a a ≥≥ b b ; a + ; a + b >b > 00
Le Le : (1, 1); : (1, 1); mm = 3= 3QQ : (2, 0); : (2, 0); mm = 4= 4CaCa : (2, 1); : (2, 1); mm = 7= 7
1.1. M. V. Diudea, M. V. Diudea, Studia Univ. BabesStudia Univ. Babes--BolyaiBolyai, 2003, 48, 3, 2003, 48, 3--21212.2. M. Goldberg, M. Goldberg, Tohoku Math. JTohoku Math. J., 1937, ., 1937, 4343, 104, 104--108.108.
Ca Ca ((M M ) = ) = TrTrP P 55((PP55((M M ))))
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CapraCapra
77Ca: Ca: (2, 1)(2, 1)Septupling (Capra) Septupling (Capra) 44Q:Q: (2, 0)(2, 0)Quadrupling (Chamfering) Quadrupling (Chamfering) 33Le: Le: (1, 1)(1, 1)Tripling (Leapfrog )Tripling (Leapfrog )11II: (1,0): (1,0)Identity Identity
mmSymbolSymbolOperationOperation
GoldbergGoldberg factors factors mm by operations on a 3by operations on a 3--valent mapvalent map
The The mm factor is also related to the formula giving factor is also related to the formula giving the volume of truncated pyramid, of height the volume of truncated pyramid, of height h h : :
VV = = mhmh/3/3coming from the ancient Egypt.coming from the ancient Egypt.
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Ca Ca ((MM) =) =TrTrP P 55((PP55((M M )), )), examplesexamples
Square faceSquare face
.E2(M) P5(M) TrP5(P5(M))
.... . . . .
....
.... ....
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Theorem onTheorem on Ca Ca ((M M ))
•• The vertex multiplication ratio inThe vertex multiplication ratio in Ca Ca ((M M )) iiss22dd0 0 ++ 11 irrespective of the tiling type ofirrespective of the tiling type of MM..
•• DemonstrationDemonstration: Observe that, for each vertex of : Observe that, for each vertex of MM, , 22dd00 new vertices result in new vertices result in Ca Ca ((M M )) and and the old vertexthe old vertex isis
preservedpreserved, thus demonstrating the theorem:, thus demonstrating the theorem:11
vv = 2= 2dd00vv00 + + vv00v v //vv00 = (2= (2dd00+1)+1)vv0 0 //vv00 = 2= 2dd00+1+1
1. M. V. Diudea, 1. M. V. Diudea, FormaForma, 2004 (submitted)., 2004 (submitted).
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Capra,Capra, continuedcontinued
TheThe transformed parameters are:transformed parameters are:11
Ca Ca ((M M ):): vv 11 = (2= (2dd00+1)+1)vv0 0 ==vv0 0 + 2+ 2ee0 0 + + ss00ff00ee = 7= 7ee0 0 = 3= 3ee0 0 + 2+ 2ss00ff00ff = (s= (s00+1)+1)ff00
It involves rotation byIt involves rotation by ππ/2/2ss00 of the parent facesof the parent faces
1.1. M. V. Diudea, M. V. Diudea, Studia Univ. BabesStudia Univ. Babes--BolyaiBolyai, 2003, 48, 3, 2003, 48, 3--2121
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CaCann ((M M );); Iterative operationIterative operation
dd00 > 3> 3vvnn = 8= 8vvn n --11 –– 77vvn n --22; ; n n ≥≥ 22
dd00 = 3= 3vvnn = 7= 7nn ⋅⋅ vv0 0 eenn = 7= 7n n ⋅⋅ ee00 = 7= 7nn ⋅⋅ 33vv0 0 /2/2ffnn = = ff00 + (7+ (7nn --1)1)⋅⋅vv0 0 /2/2
Capra,Capra, continuedcontinued
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Capra, Capra, continuedcontinued
•• CaCa insulates any face of insulates any face of MM by its own by its own hexagons, which hexagons, which are not sharedare not shared with any with any old face (in contrast to old face (in contrast to LeLe or or Q Q ).).
•• In case of a In case of a 33--valentvalent regular map the regular map the vertex multiplication ratio by Capra is vertex multiplication ratio by Capra is 77. .
•• Maps of Maps of d d 00 >> 33 are not regular anymore. are not regular anymore.
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Capra Capra -- ChiralChiral, , continuedcontinued
Enantiomeric pair of the Enantiomeric pair of the Ca Ca ((C C )), in Schlegel projection, in Schlegel projection
Since Since PP55 can be done either clockwise or countercan be done either clockwise or counter--clockwise, it resultsclockwise, it resultsin an in an enantiomericenantiomeric pair: pair: CaS CaS ((M M ) and ) and CaR CaR ((M M ), in terms of ), in terms of the the sinister/rectussinister/rectus stereochemical isomers stereochemical isomers
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CaR CaR ((CaS CaS ((T T )))); ; NN = 196= 196Ca Ca ((T T )); ; NN = 28= 28
CapraCapra, , examplesexamples
The sequence The sequence CaS CaS ((CaS CaS ((M M )))) results in a results in a twistedtwisted transform, while transform, while CaR CaR ((CaS CaS ((M M )))) will will straighten straighten the structure.the structure.
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CaR CaR ((CaS CaS ((C C )))); ; NN = 392= 392Ca Ca ((C C )); ; NN = 56= 56
CapraCapra, , examplesexamplesThe sequence The sequence Du Du ((Op Op ((Ca Ca ((M M )))))) is just the snub is just the snub Sn Sn ((MM)), , being this transform a being this transform a chiralchiral one. one.
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CapraCapra, , examplesexamples
Enantiomeric pair of a Enantiomeric pair of a Ca Ca (SWNT)(SWNT)
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Capra Capra -- OpenOpenThe The OpenOpen operation operation OpOpnn can be written as:can be written as:
OpOpn n ((Ω Ω ((M M )) = )) = EEn n Ω Ω ((M M ))EEn n ΩΩ is the is the n n --homeomorphichomeomorphic transformation of the transformation of the edges edges bounding the parentbounding the parent--like faces, like faces, namely those resulted by namely those resulted by
the the ΩΩ operation.operation.
In case In case Ω Ω ((M M ) = ) = Ca Ca ((M M ) ) the resulting open map has all the resulting open map has all polygons of the polygons of the same (6+same (6+nn) size) size. It is the . It is the only knownonly knownoperationoperation leading to a leading to a Platonic tessellationPlatonic tessellation in in
open/infinite objects.open/infinite objects.
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Capra Capra –– Open,Open, continuedcontinued
TheThe transformed parameters are:transformed parameters are:11
Op Op ((Ca Ca ((M M )):)): vv OpOp = = v v + s+ s00ff0 0 ==vv0 0 + 6+ 6e e 0 0 ee OpOp = 9= 9e e 0 0 f f OpOp = = ff --ff00 = s= s00ff00
1.1. M. V. Diudea, M. V. Diudea, Studia Univ. BabesStudia Univ. Babes--BolyaiBolyai, 2003, 48, 3, 2003, 48, 3--2121
The open (transformed) maps The open (transformed) maps cannot longer be embeddedcannot longer be embedded in in a surface of a surface of genus zerogenus zero ((e.ge.g., in the plane or the sphere).., in the plane or the sphere).
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Capra Capra -- OpenOpen, , continuedcontinued
Open polyhedraOpen polyhedra are embedded in surfaces are embedded in surfaces of of negativenegative Euler Euler χχ values and values and gg > 1> 1
The The genusgenus gg of an of an open Capraopen Capra object is calculable as:object is calculable as:
The spherical character of the parent polyhedron involves the EuThe spherical character of the parent polyhedron involves the Euler ler relation written as:relation written as:
The number of The number of parent facesparent faces, which , which equals that of open facesequals that of open faces, is:, is:
thus demonstrating the thus demonstrating the gg ––formulaformula, which can be , which can be generalisedgeneralised for for any any open objectopen object..
2/2/)e2( 000 fvg =+−=
gevfevMCaOp OpOpOp 2-2)))((( 00 =−=+−=χ
2000 =+− fev
000 2 evf +−=
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Capra Capra -- OpenOpen, , continuedcontinued
LLattices with attices with gg > 1> 1 will have will have negativenegativeand consequently and consequently negative curvaturenegative curvature. .
The The genus genus of the five of the five PlatonicPlatonic solids transformed by solids transformed by
is: is: 22 (Tetrahedron); (Tetrahedron);
33 (Cube); (Cube);
44 (Octahedron); (Octahedron);
66 (Dodecahedron) and (Dodecahedron) and
1010 (Icosahedron)(Icosahedron)
))(( MOpχ
))(( MCaOp
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Op Op ((Ca Ca ((C C )))); ; SS = 2.171 = 2.171 NN = 80; = 80; EE = 108; = 108; FF77 = 24; = 24; gg = 3 = 3
Op Op ((Ca Ca ((T T )))); ; SS = 10.432= 10.432NN = 40; = 40; EE = 54; = 54; FF77 = 12; = 12; gg = 2= 2
Capra Capra -- OpenOpen, , examplesexamples
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CaR CaR ((Op Op ((CaS CaS ((C C )))))); ; S = 0.428S = 0.428N = 464; E = 660; F = 192; g = 3; N = 464; E = 660; F = 192; g = 3;
CaR CaR ((Op Op ((CaS CaS ((T T )))))); ; S = 1.114S = 1.114N N = 232;= 232; E E = 330;= 330; F F = 96;= 96; g g = 2= 2
Capra Capra -- OpenOpen, , examplesexamples
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Op Op ((Ca Ca ((D D )))); ; S S = 1.574= 1.574N N = 200; = 200; E E = 270; = 270; FF7 7 = 60;= 60; g g = 6 = 6
Ca Ca ((D D )); ; N = 140N = 140
Capra Capra -- OpenOpen, , examplesexamples
Op Op ((Ca Ca ((M M )))) leads to leads to all heptagonall heptagon coveringcovering of negatively curved unitsof negatively curved units
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CaRCaR(C(C260260); ); NN = 1820= 1820CC260260 ; (; (IIhh))
Capra Capra -- OpenOpen, , examplesexamples
The The FowlerFowler’s phantasmagoric fullerene ’s phantasmagoric fullerene CC260260, covered only by , covered only by pentagons and heptagons and its pentagons and heptagons and its CaCa transformtransform
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Capra Capra -- OpenOpen, , examplesexamples
CaR CaR ((Op Op ((CaS CaS ((DD))))))
NN = 1160; = 1160; EE = 1650; = 1650; FF = 480; g = 6; = 480; g = 6; SS = 0.335= 0.335
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Capra Capra -- OpenOpen
Ca Ca ((SupraSupra--D D ((Op Op ((Ca Ca ((T T )))))))); ; SS = 1.075= 1.075NN = 4100; = 4100; gg = 21 = 21
SupraSupra--D D ((Op Op ((Ca Ca ((T T )))))); ; S = S = 7.876 7.876 N N = 620;= 620; E E = 900;= 900; FF7 7 = 240;= 240; g g = 21= 21
The building block The building block Op Op ((Ca Ca ((T T )),)), enables construction of a enables construction of a suprasupra--molecularmolecular(open) (open) dodecahedrondodecahedron,,11 a multi torus of a multi torus of genus 21genus 21, entirely covered by , entirely covered by heptagons heptagons FF77 ((Platonic Platonic tessellation)tessellation)
1. M. V. Diudea, 1. M. V. Diudea, FormaForma, 2004 (submitted), 2004 (submitted)
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POAV POAV –– Strain EnergyStrain Energy
θθp p = = θθσπσπ -- 9090oo pyramidalizationpyramidalization angle angle
SESE = 200(= 200(θθp p ))2 2 strain energystrain energy120 120 -- (1/3) (1/3) ΣΣθθij ij deviation to planarity deviation to planarity
In theIn the POAV1POAV1 theorytheory1,21,2 the the ππ--orbital axis vector makes orbital axis vector makes equal angles to the three equal angles to the three σσ--bonds of the spbonds of the sp22 carbon:carbon:
1. R.C. Haddon, 1. R.C. Haddon, J. Am. Chem. SocJ. Am. Chem. Soc., 112, 3385 (1990).., 112, 3385 (1990).2. R.C. Haddon, 2. R.C. Haddon, J. Phys. Chem. AJ. Phys. Chem. A, 105, 4164 (2001). , 105, 4164 (2001).
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Capra Capra -- Open Open -- LeapfrogLeapfrog
Le Le ((Op Op ((Ca Ca ((C C ))))))NN = 240; = 240; EE = 348; = 348; FF = 104; = 104; gg = 3 = 3
Le Le ((Op Op ((Ca Ca ((T T ))))))NN = 120; = 120; EE = 174; = 174; FF = 52; = 52; gg = 2 = 2
The sequence The sequence Le Le ((Op Op ((Ca Ca ((MM)))))) enables a covering by disjoint azulenic (5,7) unitsenables a covering by disjoint azulenic (5,7) units11
1. M. V. Diudea, 1. M. V. Diudea, FormaForma, 2004 (submitted), 2004 (submitted)
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Capra Capra -- Open Open -- LeapfrogLeapfrog
SupraSupra--((azulenicazulenic))--D D ((Le Le ((Op Op ((CaCa((TT))))))))N = 2400; g = 21N = 2400; g = 21
Le Le ((Op Op ((Ca Ca ((D D ))))))NN = 600; = 600; EE = 870; = 870; FF = 260; = 260; gg = 6= 6
The sequence The sequence Le Le ((Op Op ((Ca Ca ((MM)))))) enables a covering by disjoint azulenic (5,7) unitsenables a covering by disjoint azulenic (5,7) units11
1. M. V. Diudea, 1. M. V. Diudea, FormaForma, 2004 (submitted), 2004 (submitted)
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RetroRetro--CapraCapra
PP--5a5a((DD);); NN = 80= 80Ca Ca ((DD); ); NN = 140= 140
MM0 0 = P= P--55(TrTr--(P5(P5))(M(M11)))) = = EE--22((PP--5a5a(M(M11)) ))
Delete the smallest faces and continue with Delete the smallest faces and continue with EE--22
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Septupling OperationsSeptupling Operations
•• FormulasFormulas
)())(()( 51 5 MCaMPTrMS P ==
))(( 4)3,1(2 MEJS +−=
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SS11 & & SS22 OperationsOperations
OpOp22aa((SS22((C C )) )) SS22((C C ) ) EE44((C C ))
OpOp((SS11((C C ))))SS11((C C ))PP55((C C ))
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Lattice counting by the Lattice counting by the SeptuplingSeptupling--OpenOpensequence of map operationssequence of map operations
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OperationOperationParameter Parameter
000000 )12(2 vdfsevv +=++=07ee =
000 ffsf +=)(1 MS
))(( 1 MSOp0000 )13( vdfsvvOp +=+=
09eeOp =000 fsfffOp =−=
00 )12( vdv +=07ee =
000 ffsf +=)(2 MS
))(( 22 MSOp a00 )14( vdvOp +=
011eeOp =00 fsfOp =
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Septupling Septupling SS22
SS2 2 ––OpOp22aa ((T T ); ); NN = 52= 52SS22((T T ); ); NN = 28= 28
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Septupling Septupling SS2 2 -- IterativeIterative
SSSSSS2 2 ((T T ); ); NN = 1372 = 4 x 7= 1372 = 4 x 733SSSS2 2 ((T T ); ); NN = 196 = 4 x 7= 196 = 4 x 722
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Septupling Septupling SS22
SS2 2 ((O O ); ); NN = 54 = 6 x 9= 54 = 6 x 9SS2 2 ((C C ); ); NN = 56 = 8 x 7= 56 = 8 x 7
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Septupling Septupling SS2 2 -- RacemicRacemic
SS2 2 --OpOpR R ((C C ); ); NN = 104= 104SS2 2 --OpOpSS ((C C ); ); NN = 104= 104
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Iterative lattice counting by Iterative lattice counting by SeptuplingSeptupling
)(, MS niCase:Case: 30 =d
07 vvn
n ⋅=
07 een
n ⋅=
000 6/)()17( ffsfn
n +⋅−=
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Septupling Septupling SS2 2 –– IterativeIterativeFractalizationFractalization
SS22SS22SS2 2 ((C C ); ); NN = 2744 = 8 x 7= 2744 = 8 x 733SS22SS2 2 ((C C ); ); NN = 392 = 8 x 7= 392 = 8 x 722
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Septupling Septupling SS2 2 –– IterativeIterativeFractalizationFractalization
SS22SS22((DD); ); NN = = 20 x 7= = 20 x 72 2 = 980= 980SS2 2 ((DD); ); NN = 140 = 20 x 7= 140 = 20 x 7
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Septupling Septupling SS2 2 –– IterativeIterativeFractalizationFractalization
SS22SS22SS22((DD); ); NN = 6860 = 20 x 7= 6860 = 20 x 733FiveFive--fold symmetryfold symmetry
SS22SS22SS22((DD); ); NN = 6860 = 20 x 7= 6860 = 20 x 722TwoTwo--fold symmetryfold symmetry
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Septupling Septupling SS2 2 –– IterativeIterativeFractalizationFractalization
SS22SS2 2 ((I I ); ); NN = 972 = 12 x 9= 972 = 12 x 922SS22((I I ); ); NN = 132 = 12 x 11= 132 = 12 x 11
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Septupling Septupling SS2 2 –– IterativeIterativeFractalizationFractalization
SS22SS22SS2 2 ((I I ); ); NN = 6852= 6852FiveFive--fold symmetryfold symmetry
SS22SS22SS22((I I ); ); NN = 6852= 6852TwoTwo--fold symmetryfold symmetry
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5252Sn(D) = Du(P5(D)) = Du(Op(Ca(D)))Snub dodecahedronSD13
Sn(C) = Du(P5(C)) = Du(Op(Ca(C )))Snub cubeSC12
Tr(ID) = Tr(Me(Sn(T )))Truncated icosidodecahedronTID11
Tr(CO) = Tr(Me(Me(T )))Truncated cuboctahedronTCO10
Me(ID) = Me(Me(I)) = Du(P4(I))RhombicosidodecahedronRID9
Me(CO) = Me(Me(C)) = Du(P4(C ))RhombicuboctahedronRCO8
Me(I) = Me(D) = Me(Sn(T ))IcosidodecahedronID7
Me(C) = Me(O)= Me(Me(T ))CuboctahedronCO6
Tr(D) = Tr(Du(Sn(T )))Truncated dodecahedronTD5
Tr(I) = Tr(Sn(T))Truncated icosahedronTI4
Tr(C) = Tr(Du(Me(T )))Truncated cubeTC3
Tr(O) = Tr(Me(T ))Truncated octahedronTO2
Tr(T )Truncated tetrahedronTT1
Du(I ) = Du(Sn(T ))DodecahedronD5
Sn(T )IcosahedronI4
Du(O)=Du(Me(T ))Cube (hexahedron)C3
Me(T )OctahedronO2
-TetrahedronT1
FormulaPolyhedronSymbol
Platonic and Archimedean polyhedra (derived from Tetrahedron)Platonic and Archimedean polyhedra (derived from Tetrahedron)