OpenMPCD::PairPotentials::WeeksChandlerAndersen< T > Class Template Reference

Weeks-Chandler-Andersen (WCA) potential. More...

#include <WeeksChandlerAndersen.hpp>

Inheritance diagram for OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >:

Collaboration diagram for OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >:

Public Member Functions
OPENMPCD_CUDA_HOST_AND_DEVICE	WeeksChandlerAndersen (const T epsilon, const T sigma)
	The constructor. More...
OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D< T >	force (const Vector3D< T > &R) const
	Returns the force vector of the interaction for a given position vector. More...
OPENMPCD_CUDA_HOST_AND_DEVICE T	potential (const Vector3D< T > &R) const
	Returns the potential of the interaction for a given position vector. More...
virtual OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D< FP >	force (const Vector3D< FP > &Rvec) const=0
	Returns the force vector of the interaction for a given position vector. More...
virtual OPENMPCD_CUDA_HOST_AND_DEVICE FP	potential (const Vector3D< FP > &Rvec) const=0
	Returns the potential of the interaction for a given position vector. More...
const OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D< FP >	forceOnR1DueToR2 (const Vector3D< FP > &r1, const Vector3D< FP > &r2) const
	Returns the force exerted on the particle at r1 due to the particle at r2. More...

Detailed Description

template<typename T = FP>
class OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >

Weeks-Chandler-Andersen (WCA) potential.

This potential has been introduced by Weeks, Chandler, and Andersen, in J. Chem. Phys. 54, 5237 (1971). DOI: 10.1063/1.1674820

It is given, as a function of the distance \( r \) of particles, and with \( \epsilon \) and \( sigma \) being parameters, by

\[ 4 * \epsilon * \left( \left( \frac{ \sigma }{ r } \right)^{12} - \left( \frac{ \sigma }{ r } \right)^{6} + \frac{ 1 }{ 4 } \right) * \theta \left( 2^{1/6} \sigma - r \right) \]

with \( \theta \left( x \right) \) being the Heaviside step function, which is \( 1 \) if \( x > 0 \), and \( 0 \) otherwise.

Definition at line 38 of file WeeksChandlerAndersen.hpp.

Constructor & Destructor Documentation

WeeksChandlerAndersen()

template<typename T = FP>

OPENMPCD_CUDA_HOST_AND_DEVICE OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >::WeeksChandlerAndersen ( const T  epsilon, const T  sigma  )

inline

The constructor.

Parameters

[in]	epsilon	The \( \epsilon \) parameter.
[in]	sigma	The \( \sigma \) parameter.

Definition at line 48 of file WeeksChandlerAndersen.hpp.

Member Function Documentation

force() [1/2]

virtual OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D<FP > OpenMPCD::PairPotentials::Base< FP >::force ( const Vector3D< T > &  Rvec ) const

pure virtualinherited

Returns the force vector of the interaction for a given position vector.

This function returns the directional derivative

\[ - \nabla_R V \left( \vec{R} \right) \]

where \( \vec{R} \) is the Rvec parameter, \( V \) is the potential as given by the potential function, and \( \nabla_R V \) is the gradient of \( V \) with respect to \( \vec{R} \).

Parameters

[in]

Rvec

The relative position vector.

force() [2/2]

template<typename T = FP>

OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D<T> OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >::force ( const Vector3D< T > &  R ) const

inline

Returns the force vector of the interaction for a given position vector.

This function returns the directional derivative

\[ - \nabla_R V \left( \vec{R} \right) \]

where \( \vec{R} \) is the R parameter, \( V \) is the potential as given by the potential function, and \( \nabla_R V \) is the gradient of \( V \) with respect to \( \vec{R} \).

Exceptions

OpenMPCD::AssertionException

If OPENMPCD_DEBUG is defined, throws if OpenMPCD::Scalar::isZero(R.getMagnitudeSquared()).

Parameters

[in]

R

The relative position vector.

Definition at line 69 of file WeeksChandlerAndersen.hpp.

forceOnR1DueToR2()

const OPENMPCD_CUDA_HOST_AND_DEVICE Vector3D<FP > OpenMPCD::PairPotentials::Base< FP >::forceOnR1DueToR2 ( const Vector3D< T > &  r1, const Vector3D< T > &  r2  ) const

inlineinherited

Returns the force exerted on the particle at r1 due to the particle at r2.

Parameters

[in]	r1	The position of the first particle.
[in]	r2	The position of the second particle.

Definition at line 65 of file PairPotentials/Base.hpp.

potential() [1/2]

virtual OPENMPCD_CUDA_HOST_AND_DEVICE FP OpenMPCD::PairPotentials::Base< FP >::potential ( const Vector3D< T > &  Rvec ) const

pure virtualinherited

Returns the potential of the interaction for a given position vector.

Parameters

[in]

Rvec

The relative position vector.

potential() [2/2]

template<typename T = FP>

OPENMPCD_CUDA_HOST_AND_DEVICE T OpenMPCD::PairPotentials::WeeksChandlerAndersen< T >::potential ( const Vector3D< T > &  R ) const

inline

Returns the potential of the interaction for a given position vector.

Exceptions

OpenMPCD::AssertionException

If OPENMPCD_DEBUG is defined, throws if OpenMPCD::Scalar::isZero(R.getMagnitudeSquared()).

Parameters

[in]

R

The relative position vector.

Definition at line 100 of file WeeksChandlerAndersen.hpp.

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The documentation for this class was generated from the following file:

• WeeksChandlerAndersen.hpp