occ::numint::GridSettings Struct Reference

Extended settings for Becke grid generation. More...

#include <grid_settings.h>

Public Member Functions
bool	operator== (const GridSettings &rhs) const =default
bool	operator!= (const GridSettings &rhs) const =default
bool	has_angular_regions () const
	Check if ORCA-style angular regions are enabled.
std::string	int_acc_string () const
	Get IntAcc description string.

Static Public Member Functions
static GridSettings	from_grid_quality (GridQuality quality)
	Create GridSettings from GridQuality enum.
static GridSettings	for_sgx (size_t angular_points=50)
	Create GridSettings for SGX/COSX seminumerical exchange.
static GridSettings	for_cosx (COSXGridLevel level)
	Create GridSettings for COSX matching ORCA's GRIDX scheme.

Public Attributes
size_t	max_angular_points = 302
	Maximum number of angular points.
size_t	min_angular_points = 110
	Minimum number of angular points.
size_t	radial_points = 50
	Number of radial points (for some methods).
double	radial_precision
	Precision for radial grid (for LMG method).
double	int_acc = 0.0
	ORCA-style IntAcc parameter (0 = not used).
bool	reduced_first_row_element_grid
	Whether to use reduced grid for H and He.
bool	treutler_alrichs_adjustment = true
PruningScheme	pruning_scheme
	Pruning scheme to use.
std::array< size_t, 5 >	angular_regions = {0, 0, 0, 0, 0}
	ORCA-style 5-region angular grid levels [region1..region5] If non-empty, overrides min/max_angular_points with per-region Lebedev counts.
int	orca_cosx_level = 0
	ORCA 6 COSX grid level (1-3; 0 = not an ORCA COSX grid).
double	partition_weight_cutoff = 0.0
	Drop partitioned points whose Becke partition weight P_A / sum_B P_B is below this (ORCA's WCut; 0 keeps every point).
bool	rounded_bragg_radii = false
	Bragg radii for the size adjustment in bohr rounded to three decimals, as ORCA tabulates them (moves H-X adjustments by ~1e-4).

Detailed Description

Extended settings for Becke grid generation.

Member Function Documentation

for_cosx()

GridSettings occ::numint::GridSettings::for_cosx ( COSXGridLevel level )

static

Create GridSettings for COSX matching ORCA's GRIDX scheme.

Creates grids matching ORCA's COSX grid levels with:

• IntAcc-based radial point count: nr = (15 * IntAcc - 40) + b * ROW
• 5-region angular pruning with Lebedev grids
• Gauss-Chebyshev quadrature with M3 mapping

Parameters

level

COSX grid level (Grid1, Grid2, or Grid3)

Returns

GridSettings configured for the specified COSX level

for_sgx()

GridSettings occ::numint::GridSettings::for_sgx ( size_t angular_points = 50 )

static

Create GridSettings for SGX/COSX seminumerical exchange.

Uses coarser grids appropriate for seminumerical exchange:

• 50 angular points (ORCA default for COSX)
• Lower radial precision (1e-5)
• No pruning for uniform coverage

Parameters

angular_points

Number of angular Lebedev grid points (default 50)

Returns

GridSettings configured for SGX/COSX

Deprecated

Use for_cosx(COSXGridLevel) instead for ORCA-compatible grids

from_grid_quality()

GridSettings occ::numint::GridSettings::from_grid_quality ( GridQuality quality )

static

Create GridSettings from GridQuality enum.

Parameters

quality

Grid quality level

Returns

GridSettings configured for the specified quality

has_angular_regions()

bool occ::numint::GridSettings::has_angular_regions ( ) const

inline

Check if ORCA-style angular regions are enabled.

int_acc_string()

std::string occ::numint::GridSettings::int_acc_string

(

)

const

Get IntAcc description string.

operator!=()

bool occ::numint::GridSettings::operator!= ( const GridSettings & rhs ) const

inlinedefault

operator==()

bool occ::numint::GridSettings::operator== ( const GridSettings & rhs ) const

inlinedefault

Member Data Documentation

angular_regions

std::array<size_t, 5> occ::numint::GridSettings::angular_regions = {0, 0, 0, 0, 0}

ORCA-style 5-region angular grid levels [region1..region5] If non-empty, overrides min/max_angular_points with per-region Lebedev counts.

int_acc

double occ::numint::GridSettings::int_acc = 0.0

ORCA-style IntAcc parameter (0 = not used).

max_angular_points

size_t occ::numint::GridSettings::max_angular_points = 302

Maximum number of angular points.

min_angular_points

size_t occ::numint::GridSettings::min_angular_points = 110

Minimum number of angular points.

orca_cosx_level

int occ::numint::GridSettings::orca_cosx_level = 0

ORCA 6 COSX grid level (1-3; 0 = not an ORCA COSX grid).

When set, the atomic grids of H-Rn are ORCA 6.1's GRIDX atomic grids (Perez-Jorda Gauss-Chebyshev + M3 radial grid, per-element scaling and shell profile; see orca_cosx_atomic_grid); heavier elements fall back to int_acc/angular_regions.

partition_weight_cutoff

double occ::numint::GridSettings::partition_weight_cutoff = 0.0

Drop partitioned points whose Becke partition weight P_A / sum_B P_B is below this (ORCA's WCut; 0 keeps every point).

pruning_scheme

PruningScheme occ::numint::GridSettings::pruning_scheme

Initial value:

=
      PruningScheme::NWChem

Pruning scheme to use.

radial_points

size_t occ::numint::GridSettings::radial_points = 50

Number of radial points (for some methods).

radial_precision

double occ::numint::GridSettings::radial_precision

Initial value:

=
      1e-12

Precision for radial grid (for LMG method).

reduced_first_row_element_grid

bool occ::numint::GridSettings::reduced_first_row_element_grid

Initial value:

=
      true

Whether to use reduced grid for H and He.

rounded_bragg_radii

bool occ::numint::GridSettings::rounded_bragg_radii = false

Bragg radii for the size adjustment in bohr rounded to three decimals, as ORCA tabulates them (moves H-X adjustments by ~1e-4).

treutler_alrichs_adjustment

bool occ::numint::GridSettings::treutler_alrichs_adjustment = true

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

• /home/runner/work/occ/occ/include/occ/numint/grid_settings.h