Structure check parameters

Parameters for checking the system structure.

calculation.structure.plot

keyword: calculation.structure.plot

possible values: true or false

default value: true

description: If is true, structure will be ploted.

calculation.structure.file

keyword: calculation.structure.file

possible values: true or false

default value: true

description: If is true, structure files will be saved.

calculation.conductance.temperature

keyword: calculation.conductance.temperature

possible values: a double value

default value: the value used in the calculation of the self-consistent Hamiltonian, or 0 if an user provided Hamiltonian is used.

description: temperature used in the Fermi function when calculating the conductance, in unit of Kelvin. Note: the Boltzmann constant k = 8.617342e-05(eV/K) = 3.1668151e-06 (Hartree/K).

an example:

calculation.conductance.temperature = 100

calculation.conductance.kSpacePoints

keyword: calculation.conductance.kSpacePoints

possible values: 3\(\times\)n double array

default value: defined in the k-point file if the file is given by the parameter conductance.kPointFile, or produced by the parameters conductance.kSpaceGridNumber and conductance.kSpaceGridShift.

description: the fractional coordinates of n transverse wave vectors which are used in the k-space integration.

an example:

calculation.conductance.kSpacePoints = [0 0 0]

calculation.conductance.kPointWeights

keyword: calculation.conductance.kPointWeights

possible values: 1\(\times\)n double array

default value: defined in the k-point file if the corresponding parameter conductance.kSpacePoints is using the k-values in the same file. Otherwise, equally weighted.

description: the weights of the k-space points in the k-space integration.

an example:

calculation.conductance.kPointWeights = [1/2 1/3 1/6]

calculation.conductance.energyPoints

keyword: calculation.conductance.energyPoints

possible values: double array

default value: determined by nanodcal according to the applied voltages, temperature, etc.

description: the energy points which are used in the energy space integration. Note that the energy values are measured from chemical potential of a lead having zero applied voltage.

an example:

calculation.conductance.energyPoints = 0:0.03:3

calculation.conductance.energyPointWeights

keyword: calculation.conductance.energyPointWeights

possible values: double array with the same length of energyPoints.

default value: no default value if the parameter energyPoints is given explicitly. Otherwise, determined by nanodcal according to the applied voltages, temperature, etc.

description: the weights used in the energy space integration. The parameter is only used when energyPoints is given explicitly.

an example:

calculation.conductance.energyPoints = ones(1,101)/3

calculation.conductance.etaSigma

keyword: calculation.conductance.etaSigma

possible values: a small double number

default value: 1e-6 Hartree

description: the small eta used in the calculation of self-energy when the GreenFunction method is chosen.

an example:

calculation.conductance.etaSigma = 1e-4

calculation.conductance.etaGF

keyword: calculation.conductance.etaGF

possible values: a small double number

default value: 0

description: the small eta used in the calculation of Greens function when the GreenFunction method is chosen.

an example:

calculation.conductance.etaGF = 1e-4

calculation.xcFunctional.calculator

keyword: calculation.xcFunctional.calculator

possible values: a structure with two fields of class and parameter

default value: determined by nanodcal

description: This input parameter defines a plug-in calculator, where the field class clarifies the name of the calculator, and the field parameter gives its construction parameter. The constructor of the plug-in calculator will be called in the following manner: calculator = constructor([cp]) where [cp] = calculation.xcFunctional.calculator.parameter

For information about how to replace this plug-in calculator, type nanodcal -help plug-in and nanodcal -api.

an example:

calculation.xcFunctional.calculator.class = XC_cell
calculation.xcFunctional.calculator.parameter.Type ...
= LDA_VWN80

calculation.xcFunctional.Lagrange

keyword: calculation.xcFunctional.Lagrange

possible values: an integer

default value: 3

description: Lagrange parameter is for 2N+1 Point Lagrange polynomial interpolation to calculate charge density gradient.

If calculation.xcFunctional.calculator is given, this parameter will not be used.

an example:

calculation.xcFunctional.Lagrange = 3