excgrid::XcFunctional Class Reference

#include <kernel.hpp>

Public Member Functions
virtual bool	UsesGradient () const =0
virtual double	ExchangeFraction () const =0
virtual XcKernelValue	Evaluate (double rhoA, double rhoB, double sigmaAa, double sigmaAb, double sigmaBb) const =0

Detailed Description

A named, composed XC functional. The consumer evaluates one kernel call per grid point through this seam; hybrids are weighted sums of the generated kernels (see docs/kernel-api.md section 4 for the shipped recipes).

Member Function Documentation

Evaluate()

virtual XcKernelValue excgrid::XcFunctional::Evaluate ( double rhoA, double rhoB, double sigmaAa, double sigmaAb, double sigmaBb ) const

pure virtual

One per-point evaluation. LDA kernels ignore the sigma inputs.

Parameters

rhoA	The alpha-spin density.
rhoB	The beta-spin density.
sigmaAa	grad(rhoA) . grad(rhoA).
sigmaAb	grad(rhoA) . grad(rhoB).
sigmaBb	grad(rhoB) . grad(rhoB).

Returns

The energy density and first derivatives.

ExchangeFraction()

virtual double excgrid::XcFunctional::ExchangeFraction ( ) const

nodiscardpure virtual

The exact-exchange fraction the consumer routes through its HF Fock path (0 for pure functionals, e.g. 0.20 for B3LYP).

Returns

The HF exchange fraction in [0, 1].

UsesGradient()

virtual bool excgrid::XcFunctional::UsesGradient ( ) const

nodiscardpure virtual

Whether the kernel consumes the sigma inputs (GGA or beyond).

Returns

True when sigma terms are present.

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

• include/excgrid/kernel.hpp