ph keywords
Phonon calculator
ph.klist
This keyword is obsolete, please refer to ph.qpointSympoints. High-symmetry k-point paths for calculating phonon structures.
type: array
size: [inf,3]
example: ph.klist = [0.0,0.0,0.0;0.0,0.0,0.5;0.0,0.0,0.5;0.0,0.5,0.5]
ph.nk
This keyword is obsolete, please refer to ph.qpointGridn. Number of total data points along high-symmetry k-points.
type: scalar
default: 20
example: ph.nk = 20
ph.qpointGridn
ph.qpointGridn is a scalar determining the total number of points along the q-point line. The q-points are distributed as uniformly as possible.
type: scalar
default: 20
example: ph.qpointGridn = 20
ph.sympoints
This keyword is obsolete, please refer to ph.qpointSympoints. List of points visited during the phonon band structure calculation. The points can be string labels or k-points in direct coordinates. If ph.klist is defined, ph.sympoints are not used. If neither is defined, a line going along the different edges of the irreducible Brillouin zone is generated.
type: cell array
example: ph.sympoints = {'L','G','X','W','K'}
ph.qpointSympoints
List of points visited during the phonon band structure calculation. The points can be string labels or k-points in direct coordinates. If it is not defined, a line going along the different edges of the irreducible Brillouin zone is generated.
type: cell array
example: ph.qpointSympoints = {'L','G','X','W','K'}
ph.labels
Labels for high-symmetry k-points. Used for ploting.
type: cell array, string
default: {'G','X'}
example: ph.labels={'G','M','K','G'}
ph.mass
Mass of atomic species. The zero components of input masses will be replaced by default ones.
type: array
size: [1,inf]
example: ph.mass = [12, 12]
ph.unitcellMass
Mass of atoms in the given unit cell.
type: array
size: [1,inf]
example: ph.unitcellMass = [12, 12]
ph.supercellDimension
Supercell size for calculating phonons.
type: array
size: [1,3]
example: ph.supercellDimension = [2,2,1]
ph.ASR
Use Acoustic Sum Rules correction (1) or not (0).
type: scalar
default: true
allowed: true,false
example: ph.ASR = true
ph.dr
Displacement of atoms for calculating forces of a displaced configuration. In unit of Bohr.
type: scalar
default: 0.2
example: ph.dr = 0.2
ph.plot
Plot phonon band structures or not.
type: scalar
default: true
allowed: true,false
example: ph.plot = true
ph.dispStartNumber
Forces calculation starts from the designated number of displaced configuration.
type: scalar
default: 1
example: ph.dispStartNumber = 1
ph.dispEndNumber
Forces calculation ends at the designated number of displaced configuration.
type: scalar
example: ph.dispEndNumber = 1
ph.mode
Working modes of the phonon code
type: string
default: 'phonon'
allowed: 'bands','displacement','dos','force sets','force
constants’,’gamma’,’phonon’,’post’,’symmetry’
example: ph.mode = 'phonon'
ph.supercellXyzFile
Use an external input for the supercell structure (units must be Angstrom).
type: string
default: []
example: ph.supercellXyzFile = 'SPOSCAR.xyz'
ph.unitCellIndex
Atom index of the unit cell structure embedded in the supercell structure.
type: array
size: [1,inf]
example: ph.unitCellIndex = [1:2]
ph.tol
Tolerance for determining whether two atoms are in the same position or not. It is unitless as the code uses fractional coordinates for symmetry operations.
type: scalar
default: 1e-05
example: ph.tol = 1e-5
ph.usePsi
Determines whether to use provided wave function in info.savepath as the initial subspace or not.
type: scalar
default: false
allowed: true,false
example: ph.usePsi = true
ph.wUnit
Units for output phonon frequencies.
type: string
default: 'THz'
allowed: 'THz','eV','meV','cm','cm-1'
example: ph.wUnit = 'THz'
ph.isMinus
Use positive-minus displaced structures or not.
type: scalar
default: true
allowed: true,false
example: ph.isMinus = true
ph.dos.projXYZ
Determines whether to compute the phonon density of states. It is only used in Phonon DOS calculation to indicate which direction is wanted. 1, 2, 3 stands for x, y, z directions, respectively.
type: array
default: []
allowed: [1,2,3]
example: ph.dos.projXYZ = 1
ph.dos.projAtom
Calculate the phonon density of states projected on specific atoms. For example, setting ph.dos.projAtom = [221,223] will project the DOS on the atoms 221 and 223. It can be combined with other conditions such as ph.dos.projXYZ. The default is [] which sums up the contributions of all atoms.
type: array
default: []
example: ph.dos.projAtom = 501:520
ph.dos.projSpecies
Calculate the phonon density of states projected on the atoms of specific species. For example, setting ph.dos.projSpecies = 2 will project the phonon DOS on the atoms of element 2. It can be combined with other conditions such as dos.projXYZ. The default is [] which sums up the contributions of all species.
type: array
default: []
example: ph.dos.projSpecies = [5,6]
ph.dos.range
1 x 2 array describing the energy range for which the phonon DOS is calculated. The unit is determined by ph.wUnit.
type: array
default: [0, 45]
example: ph.dos.range = [0,45]
ph.dos.resolution
Determines the resolution of the phonon DOS energy axis. The unit is determined by ph.wUnit.
type: scalar
default: 0.001
example: ph.dos.resolution = 0.01