Package schrodinger :: Package application :: Package matsci :: Package espresso :: Module qeinput :: Class KpointsType

Class KpointsType

 object --+    
          |    
GenericType --+
              |
             KpointsType

Class to generate QE input XML section related to k-points.

Instance Methods

[hide private]

setStructure(self, struct)
Set structure in self.struct and several other attributes: self.vecs and self.alat.

_cleanData(self, data)
Remove mutually exclusive kpoint types.

_validateKpoints(self)
Validate k-points.

list of lists of 3 floats

_generateBandPath(self, path=None, line_density=20.0)
Get list of k-points based on the (currently predefined) path.

list of 6 floats

_generateDensity(self, ngrid, force_gamma=False)
Generate k-point mesh based on unit cell dimensions.

str

__str__(self)
Return XML.

numy.array

_toCart(self, coords)
Transform k-point coordinates from fractional reciprocal to Cartesian reciprocal in the 2pi / alat units.

Inherited from GenericType: __init__, updateWithData

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __subclasshook__

Class Variables

[hide private]

DEFAULTS = {'kpts_band': False, 'kpts_band_line_density': 20, ...

KPTS_TYPES = set(['kpts_band', 'kpts_dens', 'kpts_list', 'kpts...

Properties

[hide private]

Inherited from object: __class__

Method Details

[hide private]

setStructure(self, struct)

Set structure in self.struct and several other attributes: self.vecs and self.alat.

Parameters:

struct (structure.Structure) - Structure used for k-point generation ('kpts_dens' case)

_cleanData(self, data)

Remove mutually exclusive kpoint types. Top-priority type comes from data variable.

Parameters:

data (dict) - Top-priority dictionary of settings

Overrides: GenericType._cleanData

_validateKpoints(self)

Validate k-points. See PW input file schema documentation

Parameters:

kpts_mesh (list) - List of 6 ints (nk1, nk2, nk3 and sk1, sk2, sk3)
kpts_list (list) - List of lists of 4 floats (xk_x, xk_y, xk_z, wk)

_generateBandPath(self, path=None, line_density=20.0)

Get list of k-points based on the (currently predefined) path.

Parameters:

path (list of lists of 3 floats or None) - list of k-points in reciprocal fractional coordinates
line_density (float) - Density of the k-points between 'edges'

Returns: list of lists of 3 floats

list of k-point reciprocal Cartesian coordinates

_generateDensity(self, ngrid, force_gamma=False)

Generate k-point mesh based on unit cell dimensions. A simple approach of scaling the number of divisions along each reciprocal lattice vector proportional to its length. Uses Gamma centered meshes for hexagonal cells and Monkhorst-Pack grids otherwise.

Parameters:

ngrid (int) - Grid density
force_gamma (bool) - Enforce Gamma-centered mesh

Returns: list of 6 floats

First 3 floats represent the number of kpoints in grid directions, next 3 floats, offsets in the corresponding direction

str(self)
(Informal representation operator)

Return XML.

Returns: str: XML string
Overrides: object.__str__

_toCart(self, coords)

Transform k-point coordinates from fractional reciprocal to Cartesian reciprocal in the 2pi / alat units.

Parameters:

coords (list of 3 floats) - Coordinates of the k-point

Returns: numy.array

Cartesian coordinates of the k-point

Class Variable Details

[hide private]

DEFAULTS

Value:

{'kpts_band': False,
 'kpts_band_line_density': 20,
 'kpts_dens': 0,
 'kpts_dens_force_gamma': False,
 'kpts_list': [],
 'kpts_mesh': [6, 6, 6, 1, 1, 1]}

KPTS_TYPES

Value:

set(['kpts_band', 'kpts_dens', 'kpts_list', 'kpts_mesh'])

Class KpointsType

setStructure(self, struct)

_cleanData(self, data)

_validateKpoints(self)

_generateBandPath(self, path=None, line_density=20.0)

_generateDensity(self, ngrid, force_gamma=False)

__str__(self) (Informal representation operator)

_toCart(self, coords)

DEFAULTS

KPTS_TYPES

str(self)
(Informal representation operator)