SWNT¶
-
class
sknano.core.structures.
SWNT
(*args, nx=1, ny=1, bundle_packing=None, bundle_geometry=None, **kwargs)[source] [edit on github][source]¶ Bases:
sknano.core.structures.NanotubeBundleBase
,sknano.core.structures.SWNTBase
SWNT structure class.
Parameters: - *Ch –
Either a 2-tuple of integers (i.e., *Ch = ((n, m)) or 2 integers (i.e., *Ch = (n, m) specifying the chiral indices of the nanotube chiral vector Ch=na1+ma2=(n,m).
- nx (
int
, optional) – Number of nanotubes along the x axis - ny (
int
, optional) – Number of nanotubes along the y axis - nz (
int
, optional) – Number of repeat unit cells in the z direction, along the length of the nanotube. - basis ({
list
}, optional) –List of
str
s of element symbols or atomic number of the two atom basis (default: [‘C’, ‘C’])New in version 0.3.10.
- element2 (element1,) –
Element symbol or atomic number of basis
Atom
1 and 2Deprecated since version 0.3.10: Use
basis
instead - bond (float, optional) – aCC= distance between nearest neighbor atoms. Must be in units of Angstroms.
- Lz (float, optional) –
Length of nanotube in units of Angstroms. Overrides the
nz
value.New in version 0.2.5.
Changed in version 0.4.0: Changed units from nanometers to Angstroms
- tube_length (float, optional) –
Length of nanotube in units of Angstroms. Overrides the
nz
value.Deprecated since version 0.2.5: Use
Lz
instead - fix_Lz (bool, optional) –
Generate the nanotube with length as close to the specified Lz as possible. If
True
, then non integer nz cells are permitted.New in version 0.2.6.
- verbose (bool, optional) – if
True
, show verbose output
Examples
>>> from sknano.core.structures import SWNT
Create a SWNT with Ch=(10,10) chirality.
>>> swnt = SWNT((10, 10), verbose=True) >>> print(swnt) SWNT((10, 10), nz=1) n: 10 m: 10 t₁: 1 t₂: -1 d: 10 dR: 30 N: 20 R: (1, 0) θc: 30.00° Ch: 42.60 Å T: 2.46 Å dt: 13.56 Å rt: 6.78 Å electronic_type: metallic
Change the chirality to Ch=(20,10).
>>> swnt.n = 20 >>> print(swnt) SWNT((20, 10), nz=1) n: 20 m: 10 t₁: 4 t₂: -5 d: 10 dR: 10 N: 140 R: (1, -1) θc: 19.11° Ch: 65.07 Å T: 11.27 Å dt: 20.71 Å rt: 10.36 Å electronic_type: semiconducting, type 2
Change the chirality to Ch=(20,0).
>>> swnt.m = 0 >>> print(swnt) SWNT((20, 0), nz=1) n: 20 m: 0 t₁: 1 t₂: -2 d: 20 dR: 20 N: 40 R: (1, -1) θc: 0.00° Ch: 49.19 Å T: 4.26 Å dt: 15.66 Å rt: 7.83 Å electronic_type: semiconducting, type 1
The next example defines a Ch=(10,10) hexagonally close packed (hcp) 5×3×10
SWNT
bundle.>>> swnt_bundle = SWNT((10, 10), nx=5, ny=3, nz=10, bundle_packing='hcp') >>> print(swnt_bundle) SWNT((10, 10), nx=5, ny=3, nz=10, basis=['C', 'C'], bond=1.42, bundle_packing='hcp', bundle_geometry=None)
Attributes
Ch
SWNT circumference |Ch| in Å Ch_vec
SWNT chiral vector. Lx
Axis-aligned length along the x
-axis in Angstroms.Ly
Axis-aligned length along the y
-axis in Angstroms.Lz
SWNT length Lz=Ltube in Angstroms. M
M=np−nq N
Number of graphene hexagons in nanotube unit cell. Natoms
Number of atoms in nanotube bundle. Natoms_list
list
ofNatoms
per nanotube in bundle.Natoms_per_bundle
Alias for Natoms
.Natoms_per_tube
Alias for Natoms_list
.Natoms_per_unit_cell
Number of atoms in nanotube unit cell. Ntubes
Number of nanotubes in bundle. R
Symmetry vector R=(p,q). T
Length of nanotube unit cell |T| in Å. Tvec
SWNT
translation vector.atoms
Structure Atoms
.basis
NanoStructureBase
basis objects.bundle_density
Compute the nanotube bundle density. bundle_geometry
Bundle geometry. bundle_mass
An alias for mass
.bundle_packing
Bundle packing. chiral_angle
Chiral angle θc in degrees. chiral_type
SWNT
chiral type.crystal_cell
Structure CrystalCell
.d
d=gcd dR
d_R=\gcd{(2n + m, 2m + n)} dt
Nanotube diameter d_t = \frac{|\mathbf{C}_h|}{\pi} in Å. electronic_type
SWNT electronic type. element1
Basis element 1 element2
Basis element 2 fix_Lz
bool
indicating whetherSWNTMixin.Lz
is fixed or calculated.fmtstr
Format string. lattice
Structure Crystal3DLattice
.lattice_shift
Lattice displacement vector. linear_mass_density
Linear mass density of nanotube in g/Å. m
Chiral index m. mass
Bundle mass. n
Chiral index n. nx
Number of nanotubes along the x-axis. ny
Number of nanotubes along the y-axis. nz
Number of nanotube unit cells along the z-axis. rt
Nanotube radius r_t = \frac{|\mathbf{C}_h|}{2\pi} in Å. scaling_matrix
CrystalCell.scaling_matrix
.structure
An alias to self
.t1
t_{1} = \frac{2m + n}{d_{R}} t2
t_2 = -\frac{2n + m}{d_R} tube_length
Alias for SWNT.Lz
tube_mass
An alias for mass
.unit_cell
Structure UnitCell
.unit_cell_mass
Unit cell mass in atomic mass units. unit_cell_symmetry_params
Tuple of SWNT
unit cell symmetry parameters.vdw_distance
Van der Waals distance. vdw_radius
Van der Waals radius Methods
clear
()Clear list of StructureMixin.atoms
.generate_bundle_coords
()Generate coordinates of bundle tubes. init_bundle_parameters
()Initialize bundle attributes. make_supercell
(scaling_matrix[, wrap_coords])Make supercell. rotate
(**kwargs)Rotate crystal cell lattice, basis, and unit cell. todict
()Return dict
of constructor parameters.transform_lattice
(scaling_matrix[, ...])Transform structure lattice. translate
(t[, fix_anchor_points])Translate crystal cell lattice, basis, and unit cell. - *Ch –