ParallelConjugateGradientSolver¶

class ParallelConjugateGradientSolver(boundary_conditions=None, solvent_dielectric_constant=None, gpu_acceleration=None)¶

The parallel conjugate gradient-based Poisson solver.

Parameters:

boundary_conditions (list of DirichletBoundaryCondition | NeumannBoundaryCondition | PeriodicBoundaryCondition | MultipoleBoundaryCondition) –
A list of shape (3,2) specifying the boundary conditions on the 6 surfaces of the unit cell for the configuration.
Default:
- MoleculeConfiguration: [[MultipoleBoundaryCondition()] * 2] * 3
- BulkConfiguration: [[PeriodicBoundaryCondition()] * 2] * 3
- SurfaceConfiguration:
```
[[PeriodicBoundaryCondition()] * 2,
 [PeriodicBoundaryCondition()] * 2,
 [DirichletBoundaryCondition(), NeumannBoundaryCondition()]]
```
- DeviceConfiguration:
```
[[PeriodicBoundaryCondition()] * 2,
 [PeriodicBoundaryCondition()] * 2,
 [DirichletBoundaryCondition()] * 2]
```
solvent_dielectric_constant (float) – The dielectric constant of the media surrounding the configuration. Must be a number larger than 0.
Default: 1.0
gpu_acceleration (Enabled | Disabled | Automatic) – Whether to use GPU acceleration. If set to Automatic, the solver will use the GPU if available.
Default: Automatic

boundaryConditions()¶

Returns:: The boundary conditions for the solver.
Return type:: list of DirichletBoundaryCondition | NeumannBoundaryCondition | PeriodicBoundaryCondition | MultipoleBoundaryCondition

gpuAcceleration()¶

Returns:: The GPU acceleration flag.
Return type:: Enabled | Disabled | Automatic

nlinfo()¶

Returns:: The nlinfo.
Return type:: dict

solventDielectricConstant()¶

Returns:: The solvent dielectric constant.
Return type:: float

uniqueString()¶: Return a unique string representing the state of the object.

Usage Examples¶

Define a ParallelConjugateGradientSolver with specified boundary conditions on the 6 faces:

poisson_solver = ParallelConjugateGradientSolver(
    boundary_conditions=[
        [DirichletBoundaryCondition(), NeumannBoundaryCondition()],
        [DirichletBoundaryCondition(), DirichletBoundaryCondition()],
        [PeriodicBoundaryCondition(), PeriodicBoundaryCondition()]
    ]
)

calculator = LCAOCalculator(
    poisson_solver=poisson_solver
)

Define a ParallelConjugateGradientSolver with specified boundary conditions in the A, B, and C-direction, but similar boundary conditions on opposite faces:

poisson_solver = ParallelConjugateGradientSolver(
    boundary_conditions=[
        [DirichletBoundaryCondition(), DirichletBoundaryCondition()],
        [DirichletBoundaryCondition(), DirichletBoundaryCondition()],
        [PeriodicBoundaryCondition(), PeriodicBoundaryCondition()]
    ]
)

calculator = LCAOCalculator(
    poisson_solver=poisson_solver
)

Notes¶

By setting the solvent_dielectric_constant it is possible to perform calculations of solvents. In this case the volume of the configuration is defined by inscribing each atom in a sphere of size given by the van der Waals radius of the element. Inside the volume of the configuration the dielectric constant is 1, outside the volume of the configuration the dielectric constant is equal to the value of solvent_dielectric_constant.
See also Poisson solvers.
ParallelConjugateGradientSolver supports GPU acceleration. See GPU acceleration of proprietary feature calculations.