Nanocones A classification and generation result in chemistry - - PowerPoint PPT Presentation

nanocones
SMART_READER_LITE
LIVE PREVIEW

Nanocones A classification and generation result in chemistry - - PowerPoint PPT Presentation

Introduction Classification Construction CaGe Nanocones A classification and generation result in chemistry Gunnar Brinkmann Nico Van Cleemput Combinatorial Algorithms and Algorithmic Graph Theory Department of Applied Mathematics, Computer


slide-1
SLIDE 1

Introduction Classification Construction CaGe

Nanocones

A classification and generation result in chemistry Gunnar Brinkmann Nico Van Cleemput

Combinatorial Algorithms and Algorithmic Graph Theory Department of Applied Mathematics, Computer Science and Statistics Ghent University

Brinkmann, Van Cleemput Nanocones

slide-2
SLIDE 2

Introduction Classification Construction CaGe

Outline

1

Introduction

2

Classification Technique Existence Quadrangles Cone paths

3

Construction Pseudo-convex patches Two pentagons Number of hexagons

4

CaGe

Brinkmann, Van Cleemput Nanocones

slide-3
SLIDE 3

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-4
SLIDE 4

Introduction Classification Construction CaGe

Nón lá

Brinkmann, Van Cleemput Nanocones

slide-5
SLIDE 5

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-6
SLIDE 6

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-7
SLIDE 7

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-8
SLIDE 8

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-9
SLIDE 9

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-10
SLIDE 10

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-11
SLIDE 11

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-12
SLIDE 12

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-13
SLIDE 13

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-14
SLIDE 14

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-15
SLIDE 15

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-16
SLIDE 16

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-17
SLIDE 17

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-18
SLIDE 18

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-19
SLIDE 19

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-20
SLIDE 20

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-21
SLIDE 21

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-22
SLIDE 22

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-23
SLIDE 23

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-24
SLIDE 24

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-25
SLIDE 25

Introduction Classification Construction CaGe Brinkmann, Van Cleemput Nanocones

slide-26
SLIDE 26

Introduction Classification Construction CaGe

Carbon networks

graphene nanocone nanotube

all structures infinite Brinkmann, Van Cleemput Nanocones

slide-27
SLIDE 27

Introduction Classification Construction CaGe

Definition

Nanocone (graph) A nanocone (graph) is an infinite, cubic, 3-connected, plane graph with 1 ≤ p ≤ 5 pentagonal faces and all remaining faces hexagonal.

Brinkmann, Van Cleemput Nanocones

slide-28
SLIDE 28

Introduction Classification Construction CaGe

Classification of cones

History First: D. Klein and A. Balaban (2002,2006)

Brinkmann, Van Cleemput Nanocones

slide-29
SLIDE 29

Introduction Classification Construction CaGe

Why a new classification?

an application of an abstract classification result of disordered tilings by L. Balke (1997) very easy (using Balke’s result) very easy also for other structures – you could, e.g., immediately work out the classes for quadrangle cones or even cones of more complicated periodic structures

Brinkmann, Van Cleemput Nanocones

slide-30
SLIDE 30

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Outline

1

Introduction

2

Classification Technique Existence Quadrangles Cone paths

3

Construction Pseudo-convex patches Two pentagons Number of hexagons

4

CaGe

Brinkmann, Van Cleemput Nanocones

slide-31
SLIDE 31

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Classification

Summary Infinite number of nanocones 8 (infinite) classes based on cone body

Brinkmann, Van Cleemput Nanocones

slide-32
SLIDE 32

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Classification

graphene (0 pentagons) unique structure – so 1 class only cone with 1 pentagon unique structure – so 1 class only nanotubes (6 pentagons) infinitely many structures and infinitely many equivalence classes a finite number of tubes in each class

Brinkmann, Van Cleemput Nanocones

slide-33
SLIDE 33

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Classification of cones

cone with 1 pentagon unique structure – 1 class 2 to 4 pentagons infinitely many structures – 2 classes 5 pentagons infinitely many structures – 1 class

Brinkmann, Van Cleemput Nanocones

slide-34
SLIDE 34

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Equivalent structures

Definition Two infinite structures are called equivalent iff a finite part in both of them can be removed so that the (infinite) remainders are isomorphic.

Brinkmann, Van Cleemput Nanocones

slide-35
SLIDE 35

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

isomorphic cone body ⇒ equivalent

Brinkmann, Van Cleemput Nanocones

slide-36
SLIDE 36

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths Brinkmann, Van Cleemput Nanocones

slide-37
SLIDE 37

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Each cone is equivalent to exactly one of the following cones (only caps shown)

Brinkmann, Van Cleemput Nanocones

slide-38
SLIDE 38

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Theorem (L. Balke (1997) rephrased for these circumstances) A disordered periodic tiling is up to equivalence characterized by the periodic tiling T that is disordered (the hexagonal lattice in this case) a winding number (can be neglected here) a conjugacy class of an automorphism in the symmetry group of T (rotations of p × 60 degrees)

Brinkmann, Van Cleemput Nanocones

slide-39
SLIDE 39

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Theorem Two nanocones are equivalent if and only if they correspond to the same conjugacy class of rotations in the symmetry group of the hexagonal lattice.

Brinkmann, Van Cleemput Nanocones

slide-40
SLIDE 40

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Take any closed path around the disorder. Here: llrrrlrrlrrrr. Follow the same path llrrrlrrlrrrr in the lattice. A counterclockwise rotation by 60 degrees.

Brinkmann, Van Cleemput Nanocones

slide-41
SLIDE 41

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Following two paths after each other corresponds to product of rotation. Following two paths after each other is equivalent to following one path around both disorders.

Brinkmann, Van Cleemput Nanocones

slide-42
SLIDE 42

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

This allows to determine possible equivalence classes. Example: 3 pentagons

60 60

=

60 180

x x

There are two 180 degrees rotation conjugacy classes in the symmetry group of the hexagonal lattice: rotation around the center of an edge rotation around the center of a face. So two candidate classes.

Brinkmann, Van Cleemput Nanocones

slide-43
SLIDE 43

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Both classes exist for 3 pentagons rrlrrlrrl rrlrlrrlrrlrl Balke: proof of existence for general disorders – not necessarily of the form needed here.

Brinkmann, Van Cleemput Nanocones

slide-44
SLIDE 44

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Conjugacy classes of rotations

There are 8 conjugacy classes of rotations of p × 60 degrees counterclockwise with 1 ≤ p ≤ 5: 60 degrees around center of face 120 degrees around center of face 120 degrees around vertex 180 degrees around center of face 180 degrees around center of edge 240 degrees around center of face 240 degrees around vertex 300 degrees around center of face

Brinkmann, Van Cleemput Nanocones

slide-45
SLIDE 45

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Existence of the 8 types

Brinkmann, Van Cleemput Nanocones

slide-46
SLIDE 46

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Existence of the 8 types

Brinkmann, Van Cleemput Nanocones

slide-47
SLIDE 47

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

In nanotubes there is an infinite number of these equivalence classes.

Brinkmann, Van Cleemput Nanocones

slide-48
SLIDE 48

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Quadrangle cones from hexagonal lattice

One quadrangle (unique structure) rotation of 120 = (6 − 4) × 60 degrees around center of face

Brinkmann, Van Cleemput Nanocones

slide-49
SLIDE 49

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Two quadrangles = rotation of 240 degrees Two conjugacy classes: around the center of a face around a vertex

Brinkmann, Van Cleemput Nanocones

slide-50
SLIDE 50

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths Brinkmann, Van Cleemput Nanocones

slide-51
SLIDE 51

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Does there exist a quadrangle cone corresponding to a rotation

  • f 240 degrees around a vertex?

Brinkmann, Van Cleemput Nanocones

slide-52
SLIDE 52

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

f1 f2

Brinkmann, Van Cleemput Nanocones

slide-53
SLIDE 53

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

f1 f2 C

Brinkmann, Van Cleemput Nanocones

slide-54
SLIDE 54

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

f1 f2 C

Brinkmann, Van Cleemput Nanocones

slide-55
SLIDE 55

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Further classification

In the equivalence classes for nanotubes the region with the pentagons is bounded – the parameters of the class allow to compute upper bounds for this disordered region (cap)! Aim Take the localization of the defects also into account for cones. Classify by innermost paths of a certain form.

Brinkmann, Van Cleemput Nanocones

slide-56
SLIDE 56

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths Brinkmann, Van Cleemput Nanocones

slide-57
SLIDE 57

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Definitions

“symmetric” conepath 3 3 3 3 ((lr)mr)6−p = ((lr)3r)4 “nearsymmetric” conepath 3 3 2 3 ((lr)mr)6−p−1((lr)m−1r) = ((lr)3r)3((lr)2r

Note: always 6 − p edges with two times right

Brinkmann, Van Cleemput Nanocones

slide-58
SLIDE 58

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Definitions

Assume 2 ≤ p ≤ 5 fixed. Definition A closed path of the form ((lr)mr)6−p (for some m) is called a symmetric path (for p and m). Definition A closed path of the form ((lr)mr)6−p−1((lr)m−1r) (for some m) is called a nearsymmetric path (for p and m). Definition A closed path in a cone is called a cone path if it is symmetric

  • r nearsymmetric, shares an edge with a pentagon and has
  • nly hexagons in its exterior.

Brinkmann, Van Cleemput Nanocones

slide-59
SLIDE 59

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Adding a layer of hexagons

((lr)4r)2((lr)3r) → ((lr)5r)2((lr)4r)

Brinkmann, Van Cleemput Nanocones

slide-60
SLIDE 60

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Finer classification of cones

Theorem In every cone there is a unique cone path. unless p = 2 and there is a nearsymmetric conepath. In this case there are exactly two isomorphic conepaths with isomorphic interior.

Brinkmann, Van Cleemput Nanocones

slide-61
SLIDE 61

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Finer classification of cones

Theorem So there is a 1-1 correspondence between caps (interiors of cone paths) and cones.

Brinkmann, Van Cleemput Nanocones

slide-62
SLIDE 62

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Existence of cone paths

5 2 3 2 2 1 1 1 1 1 1 1 2 2 1 1 1 1

Brinkmann, Van Cleemput Nanocones

slide-63
SLIDE 63

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Sketch of the uniqueness proof

cone a0 = 2 a3 = 2 a2 = 4 a1 = 4 hexagonal lattice e

f(e, a0, a1, a2, a3)

a0 a1 a2 a3

Brinkmann, Van Cleemput Nanocones

slide-64
SLIDE 64

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Sketch of the uniqueness proof

Method if two conepaths exist, they are of the same type and share an edge e following the two paths in the lattice from the same starting edge gives the same end edge – so f(e, a0, . . . , ak) = f(e, a′

0, . . . , a′ k)

solve the equations for the different possible variables ai

Brinkmann, Van Cleemput Nanocones

slide-65
SLIDE 65

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

Finer classification of cones

Note The corresponding result does not hold for nanotubes.

Brinkmann, Van Cleemput Nanocones

slide-66
SLIDE 66

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths

rlrlrlrlrlrllrlrlrlr = (rl)5(lr)4

Brinkmann, Van Cleemput Nanocones

slide-67
SLIDE 67

Introduction Classification Construction CaGe Technique Existence Quadrangles Cone paths Brinkmann, Van Cleemput Nanocones

slide-68
SLIDE 68

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Outline

1

Introduction

2

Classification Technique Existence Quadrangles Cone paths

3

Construction Pseudo-convex patches Two pentagons Number of hexagons

4

CaGe

Brinkmann, Van Cleemput Nanocones

slide-69
SLIDE 69

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Patch

Definition A patch is a finite, bridgeless, plane graph with three kinds of faces: 1 outer face with unrestricted size, 1 to 5 pentagons, and an unrestricted number of hexagons. Furthermore, all internal vertices have degree 3 and all other vertices have degree 2 or 3.

Brinkmann, Van Cleemput Nanocones

slide-70
SLIDE 70

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Pseudo-convex patch

Definition A pseudo-convex patch is a patch such that the cyclic sequence of degrees on the boundary does not contain two consecutive 3’s. Definition A break-edge is a boundary edge which is incident with two vertices of degree 2. A patch with p pentagons contains 6 − p break-edges.

Brinkmann, Van Cleemput Nanocones

slide-71
SLIDE 71

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Pseudo-convex patch

Interior of a cone path is a pseudo-convex patch. l → 3 r → 2

Brinkmann, Van Cleemput Nanocones

slide-72
SLIDE 72

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Outer spiral

Brinkmann-Dress, 1997 Pseudo-convex patches have an outer spiral. 6 5 7 4 11 3 8 10 2 9 1

Brinkmann, Van Cleemput Nanocones

slide-73
SLIDE 73

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Filling the boundary

Brinkmann, Van Cleemput Nanocones

slide-74
SLIDE 74

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Next pseudo-convex boundary

Brinkmann, Van Cleemput Nanocones

slide-75
SLIDE 75

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Multiple outer spirals

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 9 10 11 12 1 2 3 4 5 6 7 8 19 20 13 14 15 16 17 18 21 22 5 6 7 8 9 10 11 12 1 2 3 4 16 17 18 19 20 13 14 15 22 21 1 12 11 10 9 8 7 6 5 4 3 2 13 20 19 18 17 16 15 14 21 22 5 4 3 2 1 12 11 10 9 8 7 6 15 14 13 20 19 18 17 16 21 22 9 8 7 6 5 4 3 2 1 12 11 10 18 17 16 15 14 13 20 19 22 21

Brinkmann, Van Cleemput Nanocones

slide-76
SLIDE 76

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Starting points

Fix the starting point and starting direction Consider all equivalent starting points!

Brinkmann, Van Cleemput Nanocones

slide-77
SLIDE 77

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Starting points

Symmetric cone path Each break-edge and each direction

Brinkmann, Van Cleemput Nanocones

slide-78
SLIDE 78

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Starting points

Nearsymmetric cone path Break-edge next to shortest side and only in the direction of the shortest side

Brinkmann, Van Cleemput Nanocones

slide-79
SLIDE 79

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Minimal spiral code

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22

[3,17,19]

9 10 11 12 1 2 3 4 5 6 7 8 19 20 13 14 15 16 17 18 21 22

[11,15,17]

5 6 7 8 9 10 11 12 1 2 3 4 16 17 18 19 20 13 14 15 22 21

[7,14,20]

1 12 11 10 9 8 7 6 5 4 3 2 13 20 19 18 17 16 15 14 21 22

[11,15,17]

5 4 3 2 1 12 11 10 9 8 7 6 15 14 13 20 19 18 17 16 21 22

[3,17,19]

9 8 7 6 5 4 3 2 1 12 11 10 18 17 16 15 14 13 20 19 22 21

[7,14,20]

Brinkmann, Van Cleemput Nanocones

slide-80
SLIDE 80

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Layers

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 9 10 11 12 1 2 3 4 5 6 7 8 19 20 13 14 15 16 17 18 21 22 5 6 7 8 9 10 11 12 1 2 3 4 16 17 18 19 20 13 14 15 22 21

Brinkmann, Van Cleemput Nanocones

slide-81
SLIDE 81

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Layer by layer

1 2 3 4 5 6 7 8 9 10 11 12

Brinkmann, Van Cleemput Nanocones

slide-82
SLIDE 82

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Isolated pentagons

While constructing the pseudo-convex patch, a pentagon neighbouring a new face can only appear at two positions: at a break-edge in the previous layer, and as the last added face.

Brinkmann, Van Cleemput Nanocones

slide-83
SLIDE 83

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of cones per length of short side

3 3 4 4 5 s n s n 1 1 2 2 3 8 1 2 3 5 18 4 9 4 12 37 16 32 5 18 63 37 89 1 10 124 413 975 2 272 212 15 387 1 288 7 040 16 032 3 941 20 915 2 960 29 342 65 056 31 025 25 1 757 5 646 88 918 194 044 150 732 30 3 039 9 640 220 741 475 422 547 166 35 4 793 15 138 476 101 1 016 193 1 620 501 35 0.1s 0.4s 4.4s 9.8s 4.1s

Timings for Intel I5 processor (1.7 GHz) Brinkmann, Van Cleemput Nanocones

slide-84
SLIDE 84

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Construction of cone caps with two pentagons

All possible positions of the pentagons can be computed directly! Idea knowing the center of the rotation given by the boundary, one pentagon determines the position of the other

Brinkmann, Van Cleemput Nanocones

slide-85
SLIDE 85

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Two pentagons

Symmetric cone patches with two pentagons There are n+1

2

  • pairwise non-isomorphic cone patches with

boundary (2(23)n)4 and they have spiral code [i, 2n + i] with i ∈

  • 0, . . . ,

n+1

2

  • − 1
  • .

Nearsymmetric cone patches with two pentagons There are n + 1 pairwise non-isomorphic cone patches with boundary 2(23)n(2(23)n+1)3 and they have spiral code [i, 2n + 1 + i] with i ∈

  • n + 1, . . . , n + 2 +

n+1

2

  • , 2n + 2, . . . , 3n + 1 −

n

2

  • .

Brinkmann, Van Cleemput Nanocones

slide-86
SLIDE 86

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons

General pseudoconvex patches Bornhöft, Brinkmann, Greinus (2003) Extremal case is spiral that starts with all pentagons and then hexagons

Brinkmann, Van Cleemput Nanocones

slide-87
SLIDE 87

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons

General pseudoconvex patches Upperbounds by Bornhöft, Brinkmann, Greinus (2003) p = 1 ⇒ h ≤ b2 − 25 40 p = 2 ⇒ h ≤ b2 − 64 32 p = 3 ⇒ h ≤ b2 − 81 24 p = 4 ⇒ h ≤ b2 − 100 16 p = 5 ⇒ h ≤ b2 − 113 8

Brinkmann, Van Cleemput Nanocones

slide-88
SLIDE 88

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons in cone patches

Pentagon in boundary! ⇒ maximal spiral not possible Idea insert vertex into boundary edge of a pentagon boundary length increases by one number of faces equal upperbound on number of hexagons is one more than upperbound of original patch

Brinkmann, Van Cleemput Nanocones

slide-89
SLIDE 89

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons in cone patches

symmetric

p = 2 ⇒ h ≤ 8m2 + 10m − 5 5 p = 3 ⇒ h ≤ 9m2 + 12m − 44 16 p = 4 ⇒ h ≤ 2m2 + 3m − 12 3 p = 5 ⇒ h ≤ m2 + 2m − 28 4

nearsymmetric

p = 2 ⇒ h ≤ 8m2 + 22m + 7 5 p = 3 ⇒ h ≤ 9m2 + 24m − 32 16 p = 4 ⇒ h ≤ 2m2 + 5m − 10 3

Brinkmann, Van Cleemput Nanocones

slide-90
SLIDE 90

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons in cone patches

5 pentagons h ≤ m2 + 2m − 28 4

  • is sharp

m odd m even

Brinkmann, Van Cleemput Nanocones

slide-91
SLIDE 91

Introduction Classification Construction CaGe Pseudo-convex patches Two pentagons Number of hexagons

Number of hexagons in cone patches

2 pentagons h ≤ 8m2 + 10m − 5 5

  • (symmetric case) and

h ≤ 8m2 + 22m + 7 5

  • (nearsymmetric case) are not sharp

h ≤ 5m2 + 8m − 4 4

  • (symmetric case) and

h ≤ 5m2 + 16m + 4 4

  • (nearsymmetric case) are sharp

Brinkmann, Van Cleemput Nanocones

slide-92
SLIDE 92

Introduction Classification Construction CaGe

Outline

1

Introduction

2

Classification Technique Existence Quadrangles Cone paths

3

Construction Pseudo-convex patches Two pentagons Number of hexagons

4

CaGe

Brinkmann, Van Cleemput Nanocones

slide-93
SLIDE 93

Introduction Classification Construction CaGe

CaGe

The program can be used inside the environment CaGe: http://caagt.ugent.be/CaGe https://www.math.uni-bielefeld.de/~CaGe/ https://github.com/CaGe-graph/CaGe

Brinkmann, Van Cleemput Nanocones

slide-94
SLIDE 94

Introduction Classification Construction CaGe

What is CaGe?

Chemical and abstract Graph environment a graphical user interface for a set of commandline generators and embedders user interface written in Java generators and embedders written in C and Java (any language will do)

Brinkmann, Van Cleemput Nanocones

slide-95
SLIDE 95

Introduction Classification Construction CaGe

User interface

Having a user interface = Being a user friendly program

Brinkmann, Van Cleemput Nanocones

slide-96
SLIDE 96

Introduction Classification Construction CaGe

Example

cone -i -e p 3 4 n 6 generates all nanocones with exactly 3 isolated pentagons that have a cone path of the form 2(23)4(2(23)5)2 and adds six layers of hexagons to the patch.

Brinkmann, Van Cleemput Nanocones

slide-97
SLIDE 97

Introduction Classification Construction CaGe

And now with CaGe

Brinkmann, Van Cleemput Nanocones

slide-98
SLIDE 98

Introduction Classification Construction CaGe

3e 3e 70 6c 61 6e 61 72 5f 63 6f 64 65 3c 3c 00 6a 01 02 00 36 00 00 00 03 00 01 00 00 00 04 00 37 00 02 00 00 00 05 00 03 00 00 00 06 00 39 00 04 00 00 00 07 00 05 00 00 00 08 00 3b 00 06 00 00 00 09 00 07 00 00 00 0a 00 3d 00 08 00 00 00 0b 00 09 00 00 00 0c 00 3f 00 0a 00 00 00 0d 00 0b 00 00 00 0e 00 41 00 0c 00 00 00 0f 00 0d 00 00 00 10 00 43 00 0e 00 00 00 11 00 0f 00 00 00 12 00 45 00 10 00 00 00 13 00 11 00 00 00 14 00 47 00 12 00 00 00 15 00 13 00 00 00 16 00 49 00 14 00 00 00 17 00 15 00 00 00 18 00 4b 00 16 00 00 00 19 00 17 00 00 00 1a 00 4d 00 18 00 00 00 1b 00 19 00 00 00 1c 00 4f 00 1a 00 00 00 1d 00 1b 00 00 00 1e 00 1c 00 00 00 1f 00 51 00 1d 00 00 00 20 00 1e 00 00 00 21 00 52 00 1f 00 00 00 22 00 20 00 00 00 23 00 54 00 21 00 00 00 24 00 22 00 00 00 25 00 56 00 23 00 00 00 26 00 24 00 00 00 27 00 58 00 25 00 00 00 28 00 26 00 00 00 29 00 5a 00 27 00 00 00 2a 00 28 00 00 00 2b 00 5c 00 29 00 00 00 2c 00 2a 00 00 00 2d 00 5e 00 2b 00 00 00 2e 00 2c 00 00 00 2f 00 60 00 2d 00 00 00 30 00 2e 00 00 00 31 00 62 00 2f 00 00 00 32 00 30 00 00 00 33 00 64 00 31 00 00 00 34 00 32 00 00 00 35 00 66 00 33 00

Brinkmann, Van Cleemput Nanocones

slide-99
SLIDE 99

Introduction Classification Construction CaGe

Output

cone and the other generators in CaGe output a binary format, e.g., planar code.

Brinkmann, Van Cleemput Nanocones

slide-100
SLIDE 100

Introduction Classification Construction CaGe

Recent additions

Rotation and stepless scaling of vertices in 2D viewer Batch export of 2D images buckygen as generator for fullerenes Upgraded plantri to version 4.5 New embedder for benzenoids New generator for 5-regular plane graphs New generator for generalised fusenes Made default embedder more customisable Export for 3D printing

Brinkmann, Van Cleemput Nanocones

slide-101
SLIDE 101

Introduction Classification Construction CaGe

CaGe

The program can be used inside the environment CaGe: http://caagt.ugent.be/CaGe https://www.math.uni-bielefeld.de/~CaGe/ https://github.com/CaGe-graph/CaGe

Brinkmann, Van Cleemput Nanocones

slide-102
SLIDE 102

Introduction Classification Construction CaGe

Nanocones

A classification and generation result in chemistry Gunnar Brinkmann Nico Van Cleemput

Combinatorial Algorithms and Algorithmic Graph Theory Department of Applied Mathematics, Computer Science and Statistics Ghent University

Brinkmann, Van Cleemput Nanocones