Parameters for calculating phononBandStructure

Parameters here are for phonon band structure calculations. (It is for calculator calcPhononBandStructure)

calculation.phononBandStructure.symmetryKPoints

keyword: calculation.phononBandStructure.symmetryKPoints

possible values: cell array of a combination of the following commonly used symbols: ‘G’ for crystal structure ‘0D’; ‘G’, ‘X’, for ‘1D’; ‘G’, ‘M’, ‘K’, for 2D ‘HEXAGON’; ‘G’, ‘M’, ‘X’, for 2D ‘SQUARE’; ‘G’, ‘X’, ‘M’, ‘R’, for ‘SC’; ‘G’, ‘X’, ‘W’, ‘L’, ‘K’, for ‘FCC’; ‘G’, ‘H’, ‘N’, ‘P’, for ‘BCC’; ‘G’, ‘M’, ‘K’, ‘A’, ‘L’ for ‘HCP’; or user defined symbols.

default value: {‘G’} for crystal structure ‘0D’; {‘G’, ‘X’} for ‘1D’; {‘G’, ‘M’, ‘K’, ‘G’} for 2D ‘HEXAGON’; {‘G’, ‘X’, ‘M’, ‘G’} for 2D ‘SQUARE’; {‘G’, ‘X’, ‘M’, ‘G’, ‘R’, ‘X’} for ‘SC’; {‘G’, ‘X’, ‘W’, ‘L’, ‘G’, ‘K’, ‘X’} for ‘FCC’; {‘G’, ‘H’, ‘N’, ‘P’, ‘G’, ‘N’} for ‘BCC’; {‘G’, ‘M’, ‘K’, ‘G’, ‘A’, ‘L’} for ‘HCP’; {‘A’, ‘B’, ‘C’, ‘D’, …} for other structures or coordinatesOfTheSymmetryKPoints is given.

description: Each symbol in the cell array corresponds to a high symmetry k-point for the given crystal structure. The phonon band structure will be calculated along the line segments which connect those high symmetry points one by one, from the first all the way to the last.

Please note that for other symbols not listed above, the parameter coordinatesOfTheSymmetryKPoints must be given explicitly.

an example:

calculation.phononBandStructure.symmetryKPoints = ...
{'G' 'X' 'W' 'L' 'G' 'K' 'X'}
calculation.phononBandStructure.symmetryKPoints = ...
{'A' 'B' 'C' 'D'}

calculation.phononBandStructure.coordinatesOfTheSymmetryKPoints

keyword: calculation.phononBandStructure.coordinatesOfTheSymmetryKPoints

possible values: 3 x n double array where n is the number of symmetry k-points defined in phononBandStructure.symmetryKPoints.

default value: calculated by nanodcal for those listed structures and listed symmetry points. No default value for other structures or high symmetry points.

description: The k-space fractional coordinates of those high symmetry k-points listed in symmetryKPoints, each column corresponds to one of them.

For a k-point with coordinates k1, k2, and k3, the corresponding k-vector is k-vector = k1 x b1 + k2 x b2 + k3 x b3, where b1, b2, and b3 are defined through dot(b_i, a_j) = 2pi x delta_{i,j}, and a1, a2, a3 are the primitive cell vectors.

Please note that this parameter must be given explicitly if any of the high symmetry k-points is not among those listed above.

an example:

calculation.phononBandStructure.coordinatesOfTheSymmetryKPoints ...
= [0 0 0; 1 0 0; 0 1 0; 0 0 1]'/2

calculation.phononBandStructure.numberOfKPoints

keyword: calculation.phononBandStructure.numberOfKPoints

possible values: an integer or an integer array

default value: determined using the value of phononBandStructure.kInterval

description: If an integer, it is the total number of k points (including the two end points) used to represent the entire band structure. If an integer array, the number of k points (including the two end points) used to represent each section of the band structure between those high symmetry points.

an example:

calculation.phononBandStructure.numberOfKPoints = 100

calculation.phononBandStructure.isProjected

keyword: calculation.phononBandStructure.isProjected

possible values: true or false

default value: false

description: If true, the contributions of the x-, y-, and z-components to the band states will be calculated.

an example:

calculation.phononBandStructure.isProjected = true

calculation.phononBandStructure.plot

keyword: calculation.phononBandStructure.plot

possible values: true or false

default value: false

description: If true, a plot will be given after the calculation.

an example:

calculation.phononBandStructure.plot = true

calculation.phononBandStructure.eMin

keyword: calculation.phononBandStructure.eMin

possible values: a double number with an unit of meV or THz or /cm.

default value: 0 meV

description: minimum energy of the phonon band structure plot.

an example:

calculation.phononBandStructure.eMin = 0 THz

calculation.phononBandStructure.eMax

keyword: calculation.phononBandStructure.eMax

possible values: a double number with an unit of meV or THz or 1/cm.

default value: 100 meV

description: maximum energy of the phonon band structure plot. Note that 1 au (Hartree) = 2 Ryderberg = 2.721138343880871e+04 meV = 6.579683913066540e+03 THz = 2.194746311151877e+05 /cm

an example:

calculation.phononBandStructure.eMax = 2000 /cm