Functional Class Reference

Abstract base class for functionals. More...

#include <ExCorr_internal.h>

Inheritance diagram for Functional:

Public Member Functions
	Functional (double scaleFac=1.0)
virtual bool	needsSigma () const =0
	return true if density gradients are used
virtual bool	needsLap () const =0
	return true if laplacian of density is used (MGGA)
virtual bool	needsTau () const =0
	return true if orbital kinetic energy density is used (MGGA)
virtual bool	hasExchange () const =0
	whether this functional includes exchange
virtual bool	hasCorrelation () const =0
	whether this functional includes correlation
virtual bool	hasKinetic () const =0
	whether this functional includes kinetic energy
virtual bool	hasEnergy () const =0
	whether total energy is meaningful for this functional
virtual void	evaluate (int N, std::vector< const double * > n, std::vector< const double * > sigma, std::vector< const double * > lap, std::vector< const double * > tau, double *E, std::vector< double * > E_n, std::vector< double * > E_sigma, std::vector< double * > E_lap, std::vector< double * > E_tau) const =0
void	evaluateSub (int iStart, int iStop, std::vector< const double * > n, std::vector< const double * > sigma, std::vector< const double * > lap, std::vector< const double * > tau, double *E, std::vector< double * > E_n, std::vector< double * > E_sigma, std::vector< double * > E_lap, std::vector< double * > E_tau) const
	Call evaluate for a subset of data points:

Protected Attributes
double	scaleFac
	scale factor (to support mixing for hybrid functionals)

Detailed Description

Abstract base class for functionals.

Member Function Documentation

evaluate()

virtual void Functional::evaluate ( int  N, std::vector< const double * >  n, std::vector< const double * >  sigma, std::vector< const double * >  lap, std::vector< const double * >  tau, double *  E, std::vector< double * >  E_n, std::vector< double * >  E_sigma, std::vector< double * >  E_lap, std::vector< double * >  E_tau  ) const

pure virtual

Compute exchange-correlation energy densities and optionally gradients if E_n[0] is non-null. Note that if E_n[0] is non-null, then so must all components of E_n and E_sigma (if a GGA). All the energies and gradients must be scaled by scaleFac.

Parameters

N	number of points
n	(spin-)densities: 1 or 2 vectors for unpolarized / polarized
sigma	contracted (spin-)density gradient contractions: 1 or 3 vectors for unpolarized / polarized
lap	laplacian of (spin-)denisties
tau	kinetic energy density per psin channel (form orbitals)
E	accumulate energy density per volume
E_n	accumulate gradient w.r.t n's (if E_n[0] is non-null)
E_sigma	accumulate gradient w.r.t sigma's (if E_n[0] is non-null)
E_lap	accumulate gradient w.r.t lap's (if E_n[0] is non-null)
E_tau	accumulate gradient w.r.t tau's (if E_n[0] is non-null)

Implemented in FunctionalMGGA, FunctionalLDA, and FunctionalGGA.

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

• electronic/ExCorr_internal.h