PairPotentials Block

Defines interatomic pair potentials and cutoff information

Overview

The PairPotentials block contains details of atom types and their associated interatomic potentials, and controls the range, binning, and truncation schemes for tabulated potentials generated from these parameters.

Keywords

Keyword	Arguments	Default	Description
`CoulombTruncation`	`CoulombTruncationScheme`	`Shifted`	Select the truncation scheme to use for coulomb interactions. This is a global parameter and applies to all pair potentials.
`Delta`	`double`	`0.005`	Spacing between points to use in the tabulated pair potential. This is a global parameter and applies to all pair potentials.
`EndPairPotentials`			Indicates the end of the current `PairPotentials` block.
`ForceChargeSource`	`bool`	`false`	Forces the user-specified choice of `IncludeCoulomb` to be used (if not letting Dissolve choose automatically).
`IncludeCoulomb`	`bool`	`false`	When not letting Dissolve choose automatically, this determins whether Coulomb terms are included in the tabulated pair potentials. If `false` then the tabulated pair potentials contain only short-range contributions, with charge interactions calculated analytically from atomic charges defined in `Species`. This is a global parameter and applies to all pair potentials.
`ManualChargeSource`	`bool`	`false`	Whether the choice of pairpotential style (including charges from atom types, or taking charges from species atoms) is left to Dissolve (`false`) or the user (`true`) to decide.
`Parameters`	`Element` `name` `charge` `ShortRangeForm` `params...`	–	Define a single atomtype called `name`, assignable to any atom of the specified `Element`, with atomic `charge` and short range form and parameters. Parameters must be given in the order expected by the specified short range type. The atomic `charge` must always be supplied, but is only used if `IncludeCoulomb` is `true`.
`Range`	`double`	`15.0`	Maximum range of the pair potentials in the simulation. This is a global parameter and applies to all pair potentials.
`ShortRangeTruncation`	`ShortRangeTruncationScheme`	`Shifted`	Select the truncation scheme to use for short-range interactions. This is a global parameter and applies to all pair potentials.
`ShortRangeTruncationWidth`	`double`	`2.0`	Truncation width to use for certain short-range truncation schemes. This is a global parameter and applies to all pair potentials.

Example

PairPotentials
  Parameters  Si  Si  2.000000e+00  LJ  0.175  1.03
  Parameters  O  O  -1.000000e+00  LJ  0.165  3.5
  Range  10.000000
  Delta  0.005000
EndPairPotentials

Last modified February 24, 2023: Docs 1.0 (#1221) (6f6c04b7e)