dftsolve Keyword List

General Keywords

Mode

Type:

string

Default:

PW

This keyword controls the running mode of the GPAW.

Mode = 'PW'

Geo_optim

Type:

boolean

Default:

True

Controls execution of geometric optimization.

Geo_optim = False

Elastic_calc

Type:

boolean

Default:

False

Whether Elastic calculations are performed or not.

Elastic_calc = True

DOS_calc

Type:

boolean

Default:

False

Whether DOS calculations are performed or not.

DOS_calc = True

Band_calc

Type:

boolean

Default:

False

Whether Band calculations are performed or not.

Band_calc = False

Density_calc

Type:

boolean

Default:

False

Whether electron density calculations are performed or not.

Density_calc = True

Optical_calc

Type:

boolean

Default:

False

Whether optical calculations are performed or not. Must be used independently from DOS_calc, Band_calc, and Density_calc. See examples directory.

Optical_calc = False

Energy_min

Type:

int

Default:

-5

Unit:

eV

Minimum energy value for plotted band structure and DOS figures.

Energy_min = -10  # eV

Energy_max

Type:

int

Default:

5

Unit:

eV

Maximum energy value for plotted band structure and DOS figures.

Energy_max = 10  # eV

Localisation

Type:

str

Default:

en_UK

Language used in figures. Supported: English, Turkish, German, French, Russian, Chinese, Korean, Japanese.

Localisation = "tr_TR"

Geometric Optimization Keywords

Optimizer

Type:

str

Default:

LBFGS

Options:

LBFGS, FIRE

Energy minimization algorithm for geometry optimization. Options: LBFGS, FIRE.

Optimizer = 'FIRE'

Max_F_tolerance

Type:

float

Default:

0.05

Unit:

eV/Å

Maximum force tolerance in BFGS-style geometry optimization.

Max_F_tolerance = 0.05  # eV/Å

Max_step

Type:

float

Default:

0.2

Unit:

Å

Maximum allowed movement for a single atom.

Max_step = 0.2  # Ang

Alpha

Type:

float

Default:

70.0

Initial guess for the Hessian (curvature of the energy surface).

Alpha = 70.0

Damping

Type:

float

Default:

1.0

Calculated step is multiplied by this number before updating positions.

Damping = 1.0

Fix_symmetry

Type:

boolean

Default:

False

Preserve spacegroup symmetry during optimization.

Fix_symmetry = True

Relax_cell

Type:

list

Default:

[False, False, False, False, False, False]

Controls which components of strain will be relaxed (six components: EpsilonX, EpsilonY, EpsilonZ, ShearYZ, ShearXZ, ShearXY).

Relax_cell = [True, True, False, False, False, False]  # For an x-y 2D nanosheet

Electronic Calculations Keywords

Cut_off_energy

Type:

integer

Default:

340

Unit:

eV

Plane wave cut-off energy value. Used in PW mode.

Cut_off_energy = 500  # eV

Ground_kpts_density

Type:

float

Default:

Not used by default.

Unit:

pts per Å^-1

k-point density. If present, Ground_kpts_x/y/z are ignored (Monkhorst-Pack mesh used otherwise).

Ground_kpts_density = 2.5  # pts per Å^-1

Ground_kpts_x | Ground_kpts_y | Ground_kpts_z

Type:

int

Default:

5

Number of k-points in x, y, z directions. Ignored if Ground_kpts_density is supplied.

Ground_kpts_x = 5
Ground_kpts_y = 5
Ground_kpts_z = 5

Ground_gpts_density

Type:

float

Default:

Not used by default.

Controls grid density for LCAO mode

Ground_gpts_density = 0.2

Ground_gpts_x | Ground_gpts_y | Ground_gpts_z

Type:

int

Default:

8

Controls g-point numbers for LCAO mode. If Ground_gpts_density is included, Ground_gpts_x/y/z are ignored.

Ground_gpts_x = 8
Ground_gpts_y = 8
Ground_gpts_z = 8

Gamma

Type:

boolean

Default:

True

Include Gamma point in band calculations.

Gamma = False

Band_path

Type:

str

Default:

'LGL'

Path of high-symmetry points in the band-structure diagram. Use G for Gamma.

Band_path = 'GMKG'

Band_npoints

Type:

int

Default:

61

Number of points between first and last high-symmetry points.

Band_npoints = 51

Setup_params

Type:

python dictionary

Default:

{}

Setup parameters for related orbitals/elements. For none, use {}. See GPAW manual on manual setups.

Setup_params = {'N': ':p,6.0'}  # eV

XC_calc

Type:

string

Default:

LDA

Options:

LDA, PBE, GLLBSC, revPBE, RPBE, HSE03, HSE06, B3LYP, PBE0

Exchange-correlation functional. Relax_cell keyword must be [False, False, False, False, False, False] with GLLBSC, HSE03 and HSE06.

XC_calc = 'PBE'

Ground_convergence

Type:

python dictionary

Default:

Convergence parameters for ground-state calculations. Use {} for defaults.

Ground_convergence = {
    'energy': 0.0005,       # eV / electron
    'density': 1.0e-4,      # electrons / electron
    'eigenstates': 4.0e-8,  # eV^2 / electron
    'forces': np.inf,
    'bands': None,
    'maximum iterations': None
}

Band_convergence

Type:

python dictionary

Default:

{'bands': 8}

Convergence parameters for band calculations.

Band_convergence = {'bands': 8, 'eigenstates': 1.0e-8}

DOS_convergence

Type:

python dictionary

Default:

{}

Convergence parameters for DOS calculations.

DOS_convergence = {'maximum iterations': 100}

Occupations

Type:

python dictionary

Default:

{}

Smearing of the occupation numbers. Options:

Occupations = {'name': 'fermi-dirac', 'width': 0.05}

Occupations = {'name': 'marzari-vanderbilt', 'width': 0.2}

Mixer_type

Type:

python import

Default:

MixerSum(0.1,3,50)

Density mixing options. See GPAW documentation on density mixing. Example values correspond to (beta, nmaxold, weight). If you have convergence problems try (0.02, 5, 100) or (0.05, 5, 50).

from gpaw import Mixer
# or
from gpaw import MixerSum
# or
from gpaw import MixerDif

Mixer_type = Mixer(0.02, 5, 100)

DOS_npoints

Type:

int

Default:

501

Number of data points for DOS.

DOS_npoints = 1001

DOS_width

Type:

float

Default:

0.1

Width of Gaussian smearing in DOS calculation. Use 0.0 for linear tetrahedron interpolation.

DOS_width = 0.0  # Using tetrahedron interpolation

Spin_calc

Type:

boolean

Default:

False

Include spin-based calculations. Set Magmom_per_atom if True.

Spin_calc = True

Magmom_per_atom

Type:

float

Default:

1.0

Unit:

µB

Magnetic moment per atom. Only relevant when Spin_calc = True.

Magmom_per_atom = 1.0

Total_charge

Type:

float

Default:

0.0

Unit:

electron charge unit

Total charge of the system. Can be positive or negative.

Total_charge = 0.0

Phonon Calculations Keywords

Phonon_PW_cutoff

Type:

int

Default:

400

Unit:

eV

Cut-off energy for phonon calculations.

Phonon_PW_cutoff = 350  # eV

Phonon_kpts_x | Phonon_kpts_y | Phonon_kpts_z

Type:

int

Default:

3

Number of k-points in x / y / z directions for phonon calculations.

Phonon_kpts_x = 5
Phonon_kpts_y = 5
Phonon_kpts_z = 5

Phonon_supercell

Type:

numpy array

Default:

np.diag([2, 2, 2])

Supercell used in phonon calculations.

Phonon_supercell = np.diag([3, 2, 2])  # 3 units in x, 2 in y and z

Phonon_displacement

Type:

float

Default:

1e-3

Unit:

Å

Displacement introduced to the supercell.

Phonon_displacement = 5e-3  # Angstrom

Phonon_path

Type:

str

Default:

LGL

Band path for phonon calculations.

Phonon_path = 'XGLG'

Phonon_npoints

Type:

int

Default:

61

Number of points between high-symmetry points for phonon calculations.

Phonon_npoints = 301

Phonon_acoustic_sum_rule

Type:

boolean

Default:

True

Apply acoustic sum rule for phonon calculations.

Phonon_acoustic_sum_rule = True

Optical Calculations Keywords

Opt_calc_type

Type:

str

Default:

BSE

Optical calculation type: random phase approximation (RPA) or Bethe-Salpeter Equation (BSE).

Opt_calc_type = 'BSE'

Opt_shift_en

Type:

float

Default:

0.0

Unit:

eV

Shift added to energy values. Works on BSE calculations only.

Opt_shift_en = 1.0  # eV

Opt_BSE_valence

Type:

Sequence of integers

Default:

range(0,3)

Valence bands used in BSE calculation.

Opt_BSE_valence = range(120,124)

Opt_BSE_conduction

Type:

Sequence of integers

Default:

`` range(4,7)``

Conduction bands used in BSE calculation.

Opt_BSE_conduction = range(124,128)

Opt_BSE_min_en

Type:

float

Default:

0.0

Unit:

eV

Start energy value for result data used in BSE calculation.

Opt_BSE_min_en = 0.0

Opt_BSE_max_en

Type:

float

Default:

20.0

Unit:

eV

End energy value for result data used in BSE calculation.

Opt_BSE_max_en = 10.0

Opt_BSE_num_of_data

Type:

int

Default:

1001

Number of data points in BSE calculation.

Opt_BSE_num_of_data = 401

Opt_num_of_bands

Type:

int

Default:

16

Number of bands used in optical calculations.

Opt_num_of_bands = 8

Opt_FD_smearing

Type:

float

Default:

0.05

Fermi-Dirac smearing for optical calculations.

Opt_FD_smearing = 0.02

Opt_eta

Type:

float

Default:

0.2

Broadening parameter eta used in dielectric function calculations (eV).

Opt_eta = 0.1

Opt_domega0

Type:

float

Default:

0.1

Options:

Δω0

Δω0 parameter for the non-linear frequency grid in dielectric function calculations (eV). See GPAW docs.

Opt_domega0 = 0.05  # eV

Opt_omega2

Type:

float

Default:

10.0

Options:

ω2

ω2 parameter for non-linear frequency grid in dielectric function calculations (eV). See GPAW docs.

Opt_omega2 = 2.0  # eV

Opt_cut_of_energy

Type:

float

Default:

10.0

Plane-wave energy cutoff in dielectric function calculations (eV). Determines dielectric matrix size.

Opt_cut_of_energy = 20.0  # eV

Opt_nblocks

Type:

int

Default:

4

Controls splitting matrices into blocks and distribution of G-vectors/frequencies over processes.

Opt_nblocks = 4