Physical objects (sisl.physics)¶
Implementations of various DFT and tight-binding related quantities are defined. The implementations range from simple Brillouin zone perspectives to self-energy calculations from Hamiltonians.
In sisl the general usage of physical matrices are considering sparse
matrices. Hence Hamiltonians, density matrices, etc. are considered
sparse. There are exceptions, but it is generally advisable to have this in mind.
Brillouin zone (brillouinzone)¶
BrillouinZone(parent[, k, weight]) |
A class to construct Brillouin zone related quantities |
MonkhorstPack(parent, nkpt[, displacement, …]) |
Create a Monkhorst-Pack grid for the Brillouin zone |
BandStructure(parent, point, division[, name]) |
Create a path in the Brillouin zone for plotting band-structures etc. |
Physical quantites¶
EnergyDensityMatrix(geometry[, dim, dtype, …]) |
Sparse energy density matrix object |
DensityMatrix(geometry[, dim, dtype, nnzpr]) |
Sparse density matrix object |
Hamiltonian(geometry[, dim, dtype, nnzpr]) |
Sparse Hamiltonian matrix object |
DynamicalMatrix(geometry[, dim, dtype, nnzpr]) |
Dynamical matrix of a geometry |
SelfEnergy(*args, **kwargs) |
Self-energy object able to calculate the dense self-energy for a given sparse matrix |
SemiInfinite(spgeom, infinite[, eta, bloch]) |
Self-energy object able to calculate the dense self-energy for a given SparseGeometry in a semi-infinite chain. |
RecursiveSI(spgeom, infinite[, eta, bloch]) |
Self-energy object using the Lopez-Sancho Lopez-Sancho algorithm |
Electrons (electron)¶
DOS(E, eig[, distribution]) |
Calculate the density of states (DOS) for a set of energies, E, with a distribution function |
PDOS(E, eig, state[, S, distribution, spin]) |
Calculate the projected density of states (PDOS) for a set of energies, E, with a distribution function |
velocity(state, dHk[, energy, dSk, degenerate]) |
Calculate the velocity of a set of states |
velocity_matrix(state, dHk[, energy, dSk, …]) |
Calculate the velocity matrix of a set of states |
berry_phase(bz_loop[, sub, eigvals, _gauge]) |
Calculate the Berry-phase on a loop using a predefined path |
wavefunction(v, grid[, geometry, k, spinor, …]) |
Add the wave-function (Orbital.psi) component of each orbital to the grid |
spin_moment(state[, S]) |
Calculate the spin magnetic moment (also known as spin texture) |
EigenvalueElectron(c[, parent]) |
Eigenvalues of electronic states, no eigenvectors retained |
EigenvectorElectron(state[, parent]) |
Eigenvectors of electronic states, no eigenvalues retained |
EigenstateElectron(state, c[, parent]) |
Eigen states of electrons with eigenvectors and eigenvalues. |
Phonons (phonon)¶
DOS(E, hw[, distribution]) |
Calculate the density of modes (DOS) for a set of energies, E, with a distribution function |
PDOS(E, mode, hw[, distribution]) |
Calculate the projected density of modes (PDOS) onto each each atom and direction for a set of energies, E, with a distribution function |
velocity(mode, hw, dDk[, degenerate]) |
Calculate the velocity of a set of modes |
displacement(mode, hw, mass) |
Calculate the real-space displacements for a given mode (in units of the characteristic length) |
EigenvaluePhonon(c[, parent]) |
Eigenvalues of phonon modes, no eigenmodes retained |
EigenvectorPhonon(state[, parent]) |
Eigenvectors of phonon modes, no eigenvalues retained |
EigenmodePhonon(state, c[, parent]) |
Eigenmodes of phonons with eigenvectors and eigenvalues. |
Distribution functions (distribution)¶
get_distribution(method[, smearing, x0]) |
Create a distribution function, Gaussian, Lorentzian etc. |
gaussian(x[, sigma, x0]) |
Gaussian distribution function |
lorentzian(x[, gamma, x0]) |
Lorentzian distribution function |
fermi_dirac(E[, kT, mu]) |
Fermi-Dirac distribution function |
bose_einstein(E[, kT, mu]) |
Bose-Einstein distribution function |
cold(E[, kT, mu]) |
Cold smearing function, Marzari-Vanderbilt, PRL 82, 16, 1999 |
Low level objects¶
The low level objects are the driven objects for a majority of the physical
objects found here. They are rarely (if ever) required to be used, but they
may be important for developers wishing to extend the functionality of sisl
using generic class-structures. For instance the Hamiltonian inherits the
SparseOrbitalBZSpin class and EigenvalueElectron inherits from Coefficient.
States¶
Coefficient(c[, parent]) |
An object holding coefficients for a parent with info |
State(state[, parent]) |
An object handling a set of vectors describing a given state |
StateC(state, c[, parent]) |
An object handling a set of vectors describing a given state with associated coefficients c |
Sparse matrices¶
SparseOrbitalBZ(geometry[, dim, dtype, nnzpr]) |
Sparse object containing the orbital connections in a Brillouin zone |
SparseOrbitalBZSpin(geometry[, dim, dtype, …]) |
Sparse object containing the orbital connections in a Brillouin zone with possible spin-components |