poisson_solver

poisson_solver.poisson_solver(grid, _dens, lmax, sph_exp=None)

Returns the spherically expanded potential \(U_{\ell m}(r)\) obtained following Becke’s procedure. (finite elements).

References

Becke, A. D. Dickson, R. M. Numerical solution of Poisson’s equation in polyatomic molecules. J. Chem. Phys. 89(5), 1988.

Parameters

• grid (BeckeGrid) – Molecular grid.

• dens (ndarray) – Array with the source density calculated in each point of the grid.

• lmax (int) – Maximum \(\ell\) order of the expansion.

Returns

Spherical expanded potential. Array with shape (nrad, lsize), where \(\ell_{size} = (\ell_{max} + 1)^2\)

Return type

U (ndarray)