Parameters for calculating eigenStates
Parameters here are for calculating the eigen states of a molecular or bulk system.
calculation.eigenStates.kSpaceGridNumber
keyword: calculation.eigenStates.kSpaceGridNumber
possible values: 3 x 1 integer array
default value: no default value
description: number of small k-space grids in each direction which, together with kSpaceGridShift, are used to produce the parameter kSpacePoints.
an example:
calculation.eigenStates.kSpaceGridNumber = [10 10 10]'
calculation.eigenStates.kSpaceGridShift
keyword: calculation.eigenStates.kSpaceGridShift
possible values: 3 x 1 or 1 x 3 array, [s_1, s_2, s_3], with each s_i a double number between 0 and 1.
default value: [0 0 0]
description: k-space grid point shift. While all s_i are set to be 0, the Gamma point is always among the k-space grid points being generated; otherwise, the k-space grid points will be shifted s_1, s_2, and s_3 grid length along their grid vector directions, respectively.
an example:
calculation.eigenStates.kSpaceGridShift = [1/2 1/2 1/2]'
calculation.eigenStates.kSpacePoints
keyword: calculation.eigenStates.kSpacePoints
possible values: 3 x n double array
default value: produced by parameter kSpaceGridNumber if it is given, otherwise, [0 0 0]’ (i.e. gamma point only)
description: the fractional coordinates of n k-space points at which the eigen states will be calculated.
an example:
calculation.eigenStates.kSpacePoints = [0 0 0]
calculation.eigenStates.numberOfBands
keyword: calculation.eigenStates.numberOfBands
possible values: 1 x 2 integer array [n1,n2] or an integer number n
default value: [1,1]
description: For a bulk system, the n1 eigen states bellow the fermi energy and n2 eigen states above the fermi energy will be calculated for each given k-point defined in kSpacePoints.
For a molecular system, the n1 eigen states bellow (including) the HOMO and n2 eigen states above (including) the LUMO will be calculated.
This calculation is not applied for systems with probes.
An integer number n can used instead of [n n] for this parameter.
an example:
calculation.eigenStates.numberOfBands = [2, 0]
calculation.eigenStates.realSpace
keyword: calculation.eigenStates.realSpace
possible values: true or false
default value: false
description: If true, real space wavefunctions of the eigen states will be calculated in a region defined by the parameters regionPosition and regionVectors.
an example:
calculation.eigenStates.realSpace = true
calculation.eigenStates.regionPosition
keyword: calculation.eigenStates.regionPosition
possible values: a 3 x 1 double array
default value: [0;0;0]
description: When realSpace is true, this parameter and regionVectors define a real space region in which wavefunctions of the eigen states will be calculated.
an example:
calculation.eigenStates.regionPosition = [1,1,1]'
calculation.eigenStates.regionVectors
keyword: calculation.eigenStates.regionVectors
possible values: a 3 x 3 double array
default value: the value of system.centralCellVectors which was used in the Hamiltonian calculation
description: When realSpace is true, this parameter and regionPosition define a real space region in which wavefunctions of the eigen states will be calculated.
an example:
calculation.eigenStates.regionVectors = eye(3)*2
calculation.eigenStates.regionGridNumber
keyword: calculation.eigenStates.regionGridNumber
possible values: 3 x 1 integer vector
default value: the value of calculation.realspacegrids.number which was used in the Hamiltonian calculation
description: the small grid number in each direction of regionVectors. It is used to define a set of real space point in the region defined by regionPosition and regionVectors, at which wavefunctions of the eigen states will be calculated.
an example:
calculation.eigenStates.regionGridNumber = [4 4 4]
calculation.eigenStates.plot
keyword: calculation.eigenStates.plot
possible values: true or false
default value: false
description: If true, a plot will be given after the calculation.
an example:
calculation.eigenStates.plot = true