DebyeHuckel

class DebyeHuckel : public feasst::ModelTwoBody

Compute energy between two point charges, $q_i$ and $q_j$ with a Debye-Huckel potential.

$U=q_i{q}_j\chi \exp (-\kappa r)/ϵr$

where $r$ is the separation distance, $\kappa$ is the inverse of the Debye screening length, $ϵ$ is the dilectric constant (dimensionless), and $\chi$ is the charge conversion factor assuming the following units:

1. length: Angstroms

2. energy: kJ/mol

3. charge: elementary

An optional smoothing_distance linearly interpolates the energy to zero at the cutoff starting at a distance of cutoff - smoothing_distance.

Avoid singularity by returning a large, positive number when $r$ is near zero.

Public Functions

void precompute(const ModelParams &existing)

Precompute model parameters based on existing model parameters.

void serialize(std::ostream &ostr) const

Output a serialized version of the existing model.

Arguments

• kappa: as described above.

• dielectric: as described above.

• smoothing_distance: as described above. Disabled when negative (default: -1).