PoissonSolver
PoissonSolver
Section Hamiltonian::Poisson
Type integer
Defines which method to use to solve the Poisson equation. Some incompatibilities apply depending on
dimensionality, periodicity, etc.
For a comparison of the accuracy and performance of the methods in Octopus, see P Garcia-Risueño,
J Alberdi-Rodriguez et al., J. Comp. Chem. 35, 427-444 (2014)
or arXiV.
Defaults:
1D and 2D: fft.
3D: cg_corrected if curvilinear, isf if not periodic, fft if periodic.
Dressed orbitals: direct_sum.
Options:
- NoPoisson:
Do not use a Poisson solver at all.
- FMM:
(Experimental) Fast multipole method. Requires FMM library.
- direct_sum:
Direct evaluation of the Hartree potential (only for finite systems).
- fft:
The Poisson equation is solved using FFTs. A cutoff technique
for the Poisson kernel is selected so the proper boundary
conditions are imposed according to the periodicity of the
system. This can be overridden by the PoissonFFTKernel
variable. To choose the FFT library use FFTLibrary
- cg:
Conjugate gradients (only for finite systems).
- cg_corrected:
Conjugate gradients, corrected for boundary conditions (only for finite systems).
- multigrid:
Multigrid method (only for finite systems).
- isf:
Interpolating Scaling Functions Poisson solver (only for finite systems).
- psolver:
Solver based on Interpolating Scaling Functions as implemented in the PSolver library.
Parallelization in k-points requires PoissonSolverPSolverParallelData = no.
Requires the PSolver external library.
- poke:
(Experimental) Solver from the Poke library.