lennardJones.C

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#include "lennardJones.H"
#include "addToRunTimeSelectionTable.H"
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
namespace Foam
{
namespace pairPotentials
{
 
// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
 
defineTypeNameAndDebug(lennardJones, 0);
 
addToRunTimeSelectionTable
(
    pairPotential,
    lennardJones,
    dictionary
);
 
 
// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
lennardJones::lennardJones
(
    const word& name,
    const dictionary& pairPotentialProperties
)
:
    pairPotential(name, pairPotentialProperties),
    lennardJonesCoeffs_(pairPotentialProperties.typeDict(typeName)),
    sigma_(lennardJonesCoeffs_.template lookup<scalar>("sigma")),
    epsilon_(lennardJonesCoeffs_.template lookup<scalar>("epsilon"))
{
    setLookupTables();
}
 
 
// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
 
scalar lennardJones::unscaledEnergy(const scalar r) const
{
    // (rIJ/sigma)^-2
    scalar ir2 = (sigma_/r)*(sigma_/r);
 
    // (rIJ/sigma)^-6
    scalar ir6 = ir2*ir2*ir2;
 
    return 4.0 * epsilon_*(ir6*(ir6 - 1.0));
}
 
 
bool lennardJones::read(const dictionary& pairPotentialProperties)
{
    pairPotential::read(pairPotentialProperties);
 
    lennardJonesCoeffs_ = pairPotentialProperties.typeDict(typeName);
 
    lennardJonesCoeffs_.lookup("sigma") >> sigma_;
    lennardJonesCoeffs_.lookup("epsilon") >> epsilon_;
 
    return true;
}
 
 
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
} // End namespace pairPotentials
} // End namespace Foam
 
// ************************************************************************* //