sknano.generators.UnrolledSWNTGenerator

class sknano.generators.UnrolledSWNTGenerator(*args, *, autogen=True, **kwargs)

Class for generating unrolled nanotube structures.

New in version 0.2.23.

Parameters:

n, m : int

Chiral indices defining the nanotube chiral vector $\mathbf{C}_{h} = n\mathbf{a}_{1} + m\mathbf{a}_{2} = (n, m)$.

nx, ny, nz : int, optional

Number of repeat unit cells in the $x, y, z$ dimensions

basis : {list}, optional

List of strs of element symbols or atomic number of the two atom basis (default: [‘C’, ‘C’])

New in version 0.3.10.

element1, element2 : {str, int}, optional

Element symbol or atomic number of basis Atom 1 and 2

Deprecated since version 0.3.10: Use basis instead

bond : float, optional

$\mathrm{a}_{\mathrm{CC}} =$ distance between nearest neighbor atoms. Must be in units of Angstroms.

Lx, Ly, Lz : float, optional

Length of bundle in $x, y, z$ dimensions in nanometers. Overrides the $n_x, n_y, n_z$ cell values.

fix_Lz : bool, optional

Generate the nanotube with length as close to the specified $L_z$ as possible. If True, then non integer $n_z$ cells are permitted.

autogen : bool, optional

if True, automatically call generate.

verbose : bool, optional

if True, show verbose output

Notes

The UnrolledSWNTGenerator class generates graphene using the nanotube unit cell defined by the chiral vector $\mathbf{C}_{h} = n\mathbf{a}_{1} + m\mathbf{a}_{2} = (n, m)$. If you want to generate graphene with an armchair or zigzag edge using length and width parameters, see the GrapheneGenerator class.

See also

GrapheneGenerator

Examples

First, load the UnrolledSWNTGenerator class.

>>> from sknano.generators import UnrolledSWNTGenerator

Now let’s generate an unrolled $\mathbf{C}_{\mathrm{h}} = (10, 5)$ SWCNT unit cell.

>>> flatswcnt = UnrolledSWNTGenerator(10, 5)
>>> flatswcnt.save()

The rendered structure looks like:

Attributes

Ch	SWNT circumference $|\mathbf{C}_h|$ in Å
Ch_vec	SWNT chiral vector.
Lx
Ly
Lz	SWNT length $L_z = L_{\mathrm{tube}}$ in nanometers.
M	$M = np - nq$
N	Number of graphene hexagons in nanotube unit cell.
Natoms	Number of atoms in nanotube.
Natoms_per_tube	Number of atoms in nanotube $N_{\mathrm{atoms/tube}}$.
Natoms_per_unit_cell	Number of atoms in nanotube unit cell.
Ntubes	Number of nanotubes.
R	Symmetry vector $\mathbf{R} = (p, q)$.
T	Length of nanotube unit cell $|\mathbf{T}|$ in Å.
Tvec	SWNT translation vector.
atoms	Structure StructureAtoms.
basis	NanoStructureBase basis atoms.
chiral_angle	Chiral angle $\theta_c$ in degrees.
chiral_type	SWNT chiral type.
crystal_cell	Structure CrystalCell.
d	$d=\gcd{(n, m)}$
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_Lx
fix_Lz
fmtstr	Format string.
lattice	Structure Crystal3DLattice.
linear_mass_density	Linear mass density of nanotube in g/nm.
m	Chiral index $m$.
n	Chiral index $n$.
nlayers	Number of layers.
nx	Number of unit cells along the $x$-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	Pointer to self.
structure_data	Alias for BaseStructureMixin.structure.
t1	$t_{1} = \frac{2m + n}{d_{R}}$
t2	$t_2 = -\frac{2n + m}{d_R}$
tube_length	Alias for SWNT.Lz
tube_mass	SWNT mass in grams.
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 BaseStructureMixin.atoms.
generate()	Generate structure data.
generate_fname([n, m, nx, nz, fix_Lx, fix_Lz])
generate_unit_cell()	Generate the nanotube unit cell.
make_supercell(scaling_matrix[, wrap_coords])	Make supercell.
read_data(*args, **kwargs)
read_dump(*args, **kwargs)
read_xyz(*args, **kwargs)
rotate(**kwargs)	Rotate crystal cell lattice, basis, and unit cell.
save([fname, outpath, structure_format, ...])	Save structure data.
todict()	Return dict of SWNT attributes.
transform_lattice(scaling_matrix[, ...])
translate(t[, fix_anchor_points])	Translate crystal cell basis.
write_data(**kwargs)
write_dump(**kwargs)
write_xyz(**kwargs)