Carbil: Difference between revisions

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== Nomenclature of the carbon flakes used ==
== Nomenclature of the carbon flakes used ==


The CDC carbon model was constructed of carbon sheets with different amount of defects.
Carbon flakes were generated by starting with four carbon atoms in fixed positions, forming three 120 degree angles, and consecutively completing three or more carbon atoms on the edge nearest to the centre to a complete hexagonal or pentagonal cycle. The location of the pentagonal cycles (defects) was chosen randomly, but then a manual selection was done and the least symmetric flakes  were discarded. Eight types with different locations of defects were chosen to construct the CDC carbon model.
8 types of carbon sheet were used:
The flakes were created on a single plane first, keeping only the topology and bond lengths in correspondence with the force field. To get their real 3-dimensional shape, they were equilibrated using a MD simulation 0.1ns long with 0.1fs timestep on room temperature (293K) in vacuo.
The initial (topological) shapes and their shapes after MD simulation are shown below.
 


=== Flake type 0 ===
=== Flake type 0 ===

Revision as of 16:30, 7 June 2010

Generation of the simulation box

Nomenclature of the carbon flakes used

Carbon flakes were generated by starting with four carbon atoms in fixed positions, forming three 120 degree angles, and consecutively completing three or more carbon atoms on the edge nearest to the centre to a complete hexagonal or pentagonal cycle. The location of the pentagonal cycles (defects) was chosen randomly, but then a manual selection was done and the least symmetric flakes were discarded. Eight types with different locations of defects were chosen to construct the CDC carbon model. The flakes were created on a single plane first, keeping only the topology and bond lengths in correspondence with the force field. To get their real 3-dimensional shape, they were equilibrated using a MD simulation 0.1ns long with 0.1fs timestep on room temperature (293K) in vacuo. The initial (topological) shapes and their shapes after MD simulation are shown below.


Flake type 0

Carbil-flake0-topo.png Carbil-flake0.png File:Carbil-flake0.xyz File:Carbil-flake0.FIELD

Flat sheet with 24 cycles and no defects.

Flake type 1

Carbil-flake1-topo.png Carbil-flake1.png File:Carbil-flake1.xyz File:Carbil-flake1.FIELD

Curved sheet with 23 normal hexagon cycles and one defect in the form of a pentagonal cycle in the middle of the flake.

Flake type 2

Carbil-flake2-topo.png Carbil-flake2.png File:Carbil-flake2.xyz File:Carbil-flake2.FIELD

Sheet with one defect near the edge.

Flake type 3

Carbil-flake3-topo.png Carbil-flake3.png File:Carbil-flake3.xyz File:Carbil-flake3.FIELD

Sheet with two defects: one on the edge, another near the edge.

Flake type 4

Carbil-flake4-topo.png Carbil-flake4.png File:Carbil-flake4.xyz File:Carbil-flake4.FIELD

Sheet with three defects located on a straight line - one in the middle, two on the edges.

Flake type 5

Carbil-flake5-topo.png Carbil-flake5.png File:Carbil-flake5.xyz File:Carbil-flake5.FIELD

Two defects near the edges.

Flake type 6

Carbil-flake6-topo.png Carbil-flake6.png File:Carbil-flake6.xyz File:Carbil-flake6.FIELD

One defect in the middle, two on the edges.

Flake type 7

Carbil-flake7-topo.png Carbil-flake7.png File:Carbil-flake7.xyz File:Carbil-flake7.FIELD

Sheet with one defect in the middle.