occ::xtb Namespace Reference

Classes
struct	AlphaBetaOccupation
	Split a total electron count into α and β occupations, e.g. More...
struct	AnisotropicEnergy
struct	AnisotropicPairGradient
struct	AnisotropicPotentials
struct	CammMoments
struct	CGenSolveResult
struct	CMatTriple
struct	CoordinationNumbersWithGradient
struct	CpcmXOptions
	Construction options for CpcmXSolvationModel. More...
class	CpcmXSolvationModel
	CPCM-X (xtb-flavoured CPCM) implicit-solvent model. More...
struct	DampedCoulomb
struct	ElementParam
struct	EwaldGammaData
class	ExternalXtbCalculator
	External-process GFN1/GFN2 driver: shells out to an xtb binary and exchanges geometry/energy via fixed-name files in the current working directory. More...
class	Gfn2Engine
class	Gfn2Parameters
struct	GlobalParam
struct	KPoint
struct	LatticeImage
struct	MultipolePairTensors
struct	MultipoleRadiiWithGradient
class	NullSolvationModel
	No-op solvation model — preserves gas-phase numbers. More...
struct	OrbitalFilling
struct	PeriodicMultipoleAO
struct	PeriodicMultipoleAOBlocks
struct	PeriodicSccOptions
struct	PeriodicSystem
struct	RepulsionEnergyGradient
struct	SccMixerState
	The quantities the SCC Hamiltonian is built from, bundled so they can be mixed as one vector between iterations. More...
struct	SccOptions
struct	ShellParam
struct	ShellTable
class	SmdSolvationModel
	SMD ("Solvation Model based on Density") for GFN-xTB. More...
struct	StoNgFit
class	TbliteCalculator
class	XtbCalculator
	In-tree GFN2-xTB calculator. More...
struct	XtbResult
	Unified GFN2-xTB SCC result. More...
class	XtbSolvationModel
	Abstract interface for an implicit-solvent contribution to a GFN-xTB SCC. More...

Typedefs
using	PeriodicSccResult = XtbResult
using	DipoleGradAO = std::array< MatTriple, 3 >
using	QuadrupoleGradAO = std::array< MatTriple, 6 >
using	CMat = Eigen::MatrixXcd
using	SccResult = XtbResult
using	SolvationSurface = occ::scrf::SolvationSurface
	Per-element solvation surface data, consumed by the crystal-growth (occ::cg) energy decomposition.
using	SolvationSurfaces = occ::scrf::SolvationSurfaces

Functions
AnisotropicEnergy	anisotropic_energy (const std::vector< core::Atom > &atoms, const Vec &q, const CammMoments &m, const DampedCoulomb &damped, const Gfn2Parameters &params)
AnisotropicPairGradient	anisotropic_pair_gradient_with_dcn (const std::vector< core::Atom > &atoms, const Vec &q, const CammMoments &m, const Vec &mp_radii, const Vec &dmp_radii_dcn, const Gfn2Parameters &params)
void	apply_anisotropic_h1_periodic (Mat &H, const Mat &S, const MatTriple &D_ket, const MatTriple &D_bra, const std::array< Mat, 6 > &Q_ket, const std::array< Mat, 6 > &Q_bra, const std::vector< int > &bf_to_atom, const AnisotropicPotentials &pot)
void	apply_anisotropic_h1_kpoint (CMat &H, const CMat &S, const CMatTriple &D_ket, const CMatTriple &D_bra, const std::array< CMat, 6 > &Q_ket, const std::array< CMat, 6 > &Q_bra, const std::vector< int > &bf_to_atom, const AnisotropicPotentials &pot)
Mat3N	anisotropic_density_pulay_gradient (const std::vector< core::Atom > &atoms, const std::vector< int > &bf_to_atom, const Mat &P, const Mat &S, const MatTriple &D_origin0, const std::array< MatTriple, 3 > &irp, const std::array< MatTriple, 6 > &irrp, const MatTriple &ovlp_grad, const AnisotropicPotentials &pot)
gto::AOBasis	build_aobasis (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params)
CammMoments	compute_camm_moments (const std::vector< core::Atom > &atoms, const std::vector< int > &bf_to_atom, const Mat &P, const Mat &S, const MatTriple &D, const std::array< Mat, 6 > &Q)
CammMoments	compute_camm_moments_periodic (const std::vector< core::Atom > &atoms, const std::vector< int > &bf_to_atom, const Mat &P, const MatTriple &D_ket, const MatTriple &D_bra, const std::array< Mat, 6 > &Q_ket, const std::array< Mat, 6 > &Q_bra)
void	accumulate_camm_kpoint (const std::vector< int > &bf_to_atom, const CMat &P_k, double w_k, const CMatTriple &D_bra_k, const std::array< CMat, 6 > &Q_bra_k, CammMoments &mom)
Vec	gfn_coordination_numbers (const std::vector< core::Atom > &atoms)
Vec	gfn_coordination_numbers_periodic (const std::vector< core::Atom > &atoms, const std::vector< LatticeImage > &lattice_translations)
CoordinationNumbersWithGradient	gfn_coordination_numbers_with_gradient (const std::vector< core::Atom > &atoms)
double	auto_ewald_alpha (double volume_bohr3)
double	ewald_real_cutoff (double alpha, double tol)
double	ewald_recip_cutoff (double alpha, double tol)
std::vector< Vec3 >	enumerate_g_vectors (const Mat3 &reciprocal_bohr, double recip_cutoff)
ShellTable	build_shell_table (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params)
Mat	klopman_ohno_gamma (const std::vector< core::Atom > &atoms, const ShellTable &shells, const Gfn2Parameters &params)
Mat3N	klopman_ohno_gamma_energy_gradient (const std::vector< core::Atom > &atoms, const ShellTable &shells, const Gfn2Parameters &params, const Mat &gamma_matrix, const Vec &qsh)
Vec	eeq_initial_shell_charges (const std::vector< core::Atom > &atoms, const ShellTable &shells, double total_charge)
Vec	eeq_initial_shell_charges_periodic (const std::vector< core::Atom > &atoms, const ShellTable &shells, const Mat3 &lattice_bohr, double total_charge)
constexpr int	spin_pair_index (int l_i, int l_j)
PeriodicSccResult	run_charge_only_periodic_scc (const PeriodicSystem &sys, const Gfn2Parameters &params, const PeriodicSccOptions &opts={})
PeriodicSccResult	run_periodic_scc_kpoints (const PeriodicSystem &sys, const Gfn2Parameters &params, const std::vector< struct KPoint > &kpoints, const PeriodicSccOptions &opts={})
Vec	compute_self_energies (const ShellTable &shells, const Vec &cn)
Mat	build_h0 (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params, const ShellTable &shells, const gto::AOBasis &basis, const Mat &overlap, const Vec &cn)
Mat3N	h0_scc_gradient (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params, const ShellTable &shells, const gto::AOBasis &basis, qm::IntegralEngine &engine, const Mat &S, const Mat &P, const Mat &W, const Vec &V_shell, const Vec &cn, const std::vector< Mat3N > &dcn, const Mat &P_spin=Mat(), const Vec &v_spin_shell=Vec())
std::vector< KPoint >	monkhorst_pack_grid (const Mat3 &reciprocal_bohr, int n1, int n2, int n3)
Vec	multipole_radii (const std::vector< core::Atom > &atoms, const Vec &cn, const Gfn2Parameters &params)
MultipoleRadiiWithGradient	multipole_radii_with_gradient (const std::vector< core::Atom > &atoms, const Vec &cn, const Gfn2Parameters &params)
DampedCoulomb	damped_multipole_coulomb (const std::vector< core::Atom > &atoms, const Vec &mp_radii, const Gfn2Parameters &params)
MultipolePairTensors	build_multipole_ewald_tensors (const PeriodicSystem &sys, const Vec &mp_radii, const Gfn2Parameters &params, double tol=1e-10, double alpha_user=0.0)
MultipolePairTensors	build_molecular_multipole_tensors (const std::vector< core::Atom > &atoms, const Vec &mp_radii, const Gfn2Parameters &params)
AnisotropicEnergy	anisotropic_energy_ewald (const std::vector< core::Atom > &atoms, const Vec &q, const CammMoments &m, const MultipolePairTensors &tensors, const Gfn2Parameters &params)
AnisotropicPotentials	anisotropic_potentials_ewald (const std::vector< core::Atom > &atoms, const Vec &q, const CammMoments &m, const MultipolePairTensors &tensors, const Gfn2Parameters &params)
MatTriple	dipole_ao_matrices (qm::IntegralEngine &engine, const Vec3 &origin=Vec3::Zero())
std::array< Mat, 6 >	quadrupole_ao_matrices (qm::IntegralEngine &engine, const Vec3 &origin=Vec3::Zero())
DipoleGradAO	dipole_ao_grad (qm::IntegralEngine &engine)
QuadrupoleGradAO	quadrupole_ao_grad (qm::IntegralEngine &engine)
AlphaBetaOccupation	alpha_beta_occupation (double n_elec, double n_unpaired)
OrbitalFilling	fermi_filling (double n_electrons, double kt, const Vec &orbital_energies)
	Fill n_electrons into one spin channel by Fermi-Dirac smearing at electronic temperature kt (this is kB·T in Hartree, not T in Kelvin).
std::vector< LatticeImage >	build_lattice_images (const Mat3 &lattice_bohr, double cutoff_bohr)
EwaldGammaData	build_ewald_data (const PeriodicSystem &sys, double tol=1e-10, double alpha_user=0.0, double residual_cutoff=0.0)
Mat	periodic_klopman_ohno_gamma (const PeriodicSystem &sys, const ShellTable &shells, const Gfn2Parameters &params, const EwaldGammaData &ewald)
Mat	periodic_klopman_ohno_gamma_direct (const PeriodicSystem &sys, const ShellTable &shells, const Gfn2Parameters &params, double cutoff_bohr)
std::vector< Mat >	periodic_overlap_blocks (const PeriodicSystem &sys, const Gfn2Parameters &params, const std::vector< LatticeImage > &translations)
std::vector< Mat >	periodic_h0_blocks (const PeriodicSystem &sys, const Gfn2Parameters &params, const std::vector< LatticeImage > &translations, const std::vector< Mat > &S_per_T, const Vec &cn)
PeriodicMultipoleAO	build_periodic_multipole_ao (const PeriodicSystem &sys, const Gfn2Parameters &params, const std::vector< LatticeImage > &translations)
PeriodicMultipoleAOBlocks	build_periodic_multipole_ao_blocks (const PeriodicSystem &sys, const Gfn2Parameters &params, const std::vector< LatticeImage > &translations)
CMatTriple	bloch_sum_triple (const std::vector< MatTriple > &per_T, const std::vector< LatticeImage > &translations, const Vec3 &k)
std::array< CMat, 6 >	bloch_sum_array6 (const std::vector< std::array< Mat, 6 > > &per_T, const std::vector< LatticeImage > &translations, const Vec3 &k)
void	apply_traceless_quadrupole_transform (std::array< Mat, 6 > &Q)
PeriodicMultipoleAO	center_multipole_ao (const std::vector< core::Atom > &atoms, const std::vector< int > &bf_to_atom, const Mat &S, const MatTriple &D_origin0, const std::array< Mat, 6 > &Q_origin0)
PeriodicMultipoleAO	build_molecular_multipole_ao (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params)
CMat	bloch_sum (const std::vector< Mat > &M_per_T, const std::vector< LatticeImage > &translations, const Vec3 &k)
Mat	bloch_sum_gamma (const std::vector< Mat > &M_per_T)
CGenSolveResult	solve_generalized_hermitian (const CMat &H, const CMat &S, double s_eps=1e-10)
double	repulsion_energy (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params)
double	repulsion_energy_periodic (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params, const std::vector< LatticeImage > &translations)
RepulsionEnergyGradient	repulsion_energy_and_gradient (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params)
SccResult	run_charge_only_scc (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params, const SccOptions &opts={})
SccResult	run_gfn2_scc (const std::vector< core::Atom > &atoms, const Gfn2Parameters &params, const SccOptions &opts={})
Mat	spin_coupling_matrix (const std::vector< core::Atom > &atoms, const ShellTable &shells, const Gfn2Parameters &params, double scale=1.0)
	On-site spin-coupling matrix W (n_shells × n_shells, Hartree), block diagonal by atom — the GFN-xTB spin interaction has no inter-atomic part.
StoNgFit	slater_to_gauss (int ng, int n, int l, double zeta, bool normalize=true)
std::string	tblite_version ()

Typedef Documentation

CMat

using occ::xtb::CMat = typedef Eigen::MatrixXcd

DipoleGradAO

using occ::xtb::DipoleGradAO = typedef std::array<MatTriple, 3>

PeriodicSccResult

using occ::xtb::PeriodicSccResult = typedef XtbResult

QuadrupoleGradAO

using occ::xtb::QuadrupoleGradAO = typedef std::array<MatTriple, 6>

SccResult

using occ::xtb::SccResult = typedef XtbResult

SolvationSurface

using occ::xtb::SolvationSurface = typedef occ::scrf::SolvationSurface

Per-element solvation surface data, consumed by the crystal-growth (occ::cg) energy decomposition.

Phase 2 unification: these are now aliases for the shared occ::scrf types — the xTB and HF/DFT solvation pipelines speak the same per-element shape.

SolvationSurfaces

using occ::xtb::SolvationSurfaces = typedef occ::scrf::SolvationSurfaces

Function Documentation

accumulate_camm_kpoint()

void occ::xtb::accumulate_camm_kpoint	(	const std::vector< int > &	bf_to_atom,
		const CMat &	P_k,
		double	w_k,
		const CMatTriple &	D_bra_k,
		const std::array< CMat, 6 > &	Q_bra_k,
		CammMoments &	mom
	)

alpha_beta_occupation()

AlphaBetaOccupation occ::xtb::alpha_beta_occupation	(	double	n_elec,
		double	n_unpaired
	)

anisotropic_density_pulay_gradient()

Mat3N occ::xtb::anisotropic_density_pulay_gradient	(	const std::vector< core::Atom > &	atoms,
		const std::vector< int > &	bf_to_atom,
		const Mat &	P,
		const Mat &	S,
		const MatTriple &	D_origin0,
		const std::array< MatTriple, 3 > &	irp,
		const std::array< MatTriple, 6 > &	irrp,
		const MatTriple &	ovlp_grad,
		const AnisotropicPotentials &	pot
	)

anisotropic_energy()

AnisotropicEnergy occ::xtb::anisotropic_energy	(	const std::vector< core::Atom > &	atoms,
		const Vec &	q,
		const CammMoments &	m,
		const DampedCoulomb &	damped,
		const Gfn2Parameters &	params
	)

anisotropic_energy_ewald()

AnisotropicEnergy occ::xtb::anisotropic_energy_ewald	(	const std::vector< core::Atom > &	atoms,
		const Vec &	q,
		const CammMoments &	m,
		const MultipolePairTensors &	tensors,
		const Gfn2Parameters &	params
	)

anisotropic_pair_gradient_with_dcn()

AnisotropicPairGradient occ::xtb::anisotropic_pair_gradient_with_dcn	(	const std::vector< core::Atom > &	atoms,
		const Vec &	q,
		const CammMoments &	m,
		const Vec &	mp_radii,
		const Vec &	dmp_radii_dcn,
		const Gfn2Parameters &	params
	)

anisotropic_potentials_ewald()

AnisotropicPotentials occ::xtb::anisotropic_potentials_ewald	(	const std::vector< core::Atom > &	atoms,
		const Vec &	q,
		const CammMoments &	m,
		const MultipolePairTensors &	tensors,
		const Gfn2Parameters &	params
	)

apply_anisotropic_h1_kpoint()

void occ::xtb::apply_anisotropic_h1_kpoint	(	CMat &	H,
		const CMat &	S,
		const CMatTriple &	D_ket,
		const CMatTriple &	D_bra,
		const std::array< CMat, 6 > &	Q_ket,
		const std::array< CMat, 6 > &	Q_bra,
		const std::vector< int > &	bf_to_atom,
		const AnisotropicPotentials &	pot
	)

apply_anisotropic_h1_periodic()

void occ::xtb::apply_anisotropic_h1_periodic	(	Mat &	H,
		const Mat &	S,
		const MatTriple &	D_ket,
		const MatTriple &	D_bra,
		const std::array< Mat, 6 > &	Q_ket,
		const std::array< Mat, 6 > &	Q_bra,
		const std::vector< int > &	bf_to_atom,
		const AnisotropicPotentials &	pot
	)

apply_traceless_quadrupole_transform()

void occ::xtb::apply_traceless_quadrupole_transform

(

std::array< Mat, 6 > &

Q

)

auto_ewald_alpha()

double occ::xtb::auto_ewald_alpha

(

double

volume_bohr3

)

bloch_sum()

CMat occ::xtb::bloch_sum	(	const std::vector< Mat > &	M_per_T,
		const std::vector< LatticeImage > &	translations,
		const Vec3 &	k
	)

bloch_sum_array6()

std::array< CMat, 6 > occ::xtb::bloch_sum_array6	(	const std::vector< std::array< Mat, 6 > > &	per_T,
		const std::vector< LatticeImage > &	translations,
		const Vec3 &	k
	)

bloch_sum_gamma()

Mat occ::xtb::bloch_sum_gamma

(

const std::vector< Mat > &

M_per_T

)

bloch_sum_triple()

CMatTriple occ::xtb::bloch_sum_triple	(	const std::vector< MatTriple > &	per_T,
		const std::vector< LatticeImage > &	translations,
		const Vec3 &	k
	)

build_aobasis()

gto::AOBasis occ::xtb::build_aobasis	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params
	)

build_ewald_data()

EwaldGammaData occ::xtb::build_ewald_data	(	const PeriodicSystem &	sys,
		double	tol = 1e-10,
		double	alpha_user = 0.0,
		double	residual_cutoff = 0.0
	)

build_h0()

Mat occ::xtb::build_h0	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params,
		const ShellTable &	shells,
		const gto::AOBasis &	basis,
		const Mat &	overlap,
		const Vec &	cn
	)

build_lattice_images()

std::vector< LatticeImage > occ::xtb::build_lattice_images	(	const Mat3 &	lattice_bohr,
		double	cutoff_bohr
	)

build_molecular_multipole_ao()

PeriodicMultipoleAO occ::xtb::build_molecular_multipole_ao	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params
	)

build_molecular_multipole_tensors()

MultipolePairTensors occ::xtb::build_molecular_multipole_tensors	(	const std::vector< core::Atom > &	atoms,
		const Vec &	mp_radii,
		const Gfn2Parameters &	params
	)

build_multipole_ewald_tensors()

MultipolePairTensors occ::xtb::build_multipole_ewald_tensors	(	const PeriodicSystem &	sys,
		const Vec &	mp_radii,
		const Gfn2Parameters &	params,
		double	tol = 1e-10,
		double	alpha_user = 0.0
	)

build_periodic_multipole_ao()

PeriodicMultipoleAO occ::xtb::build_periodic_multipole_ao	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const std::vector< LatticeImage > &	translations
	)

build_periodic_multipole_ao_blocks()

PeriodicMultipoleAOBlocks occ::xtb::build_periodic_multipole_ao_blocks	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const std::vector< LatticeImage > &	translations
	)

build_shell_table()

ShellTable occ::xtb::build_shell_table	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params
	)

center_multipole_ao()

PeriodicMultipoleAO occ::xtb::center_multipole_ao	(	const std::vector< core::Atom > &	atoms,
		const std::vector< int > &	bf_to_atom,
		const Mat &	S,
		const MatTriple &	D_origin0,
		const std::array< Mat, 6 > &	Q_origin0
	)

compute_camm_moments()

CammMoments occ::xtb::compute_camm_moments	(	const std::vector< core::Atom > &	atoms,
		const std::vector< int > &	bf_to_atom,
		const Mat &	P,
		const Mat &	S,
		const MatTriple &	D,
		const std::array< Mat, 6 > &	Q
	)

compute_camm_moments_periodic()

CammMoments occ::xtb::compute_camm_moments_periodic	(	const std::vector< core::Atom > &	atoms,
		const std::vector< int > &	bf_to_atom,
		const Mat &	P,
		const MatTriple &	D_ket,
		const MatTriple &	D_bra,
		const std::array< Mat, 6 > &	Q_ket,
		const std::array< Mat, 6 > &	Q_bra
	)

compute_self_energies()

Vec occ::xtb::compute_self_energies	(	const ShellTable &	shells,
		const Vec &	cn
	)

damped_multipole_coulomb()

DampedCoulomb occ::xtb::damped_multipole_coulomb	(	const std::vector< core::Atom > &	atoms,
		const Vec &	mp_radii,
		const Gfn2Parameters &	params
	)

dipole_ao_grad()

DipoleGradAO occ::xtb::dipole_ao_grad

(

qm::IntegralEngine &

engine

)

dipole_ao_matrices()

MatTriple occ::xtb::dipole_ao_matrices	(	qm::IntegralEngine &	engine,
		const Vec3 &	origin = Vec3::Zero()
	)

eeq_initial_shell_charges()

Vec occ::xtb::eeq_initial_shell_charges	(	const std::vector< core::Atom > &	atoms,
		const ShellTable &	shells,
		double	total_charge
	)

eeq_initial_shell_charges_periodic()

Vec occ::xtb::eeq_initial_shell_charges_periodic	(	const std::vector< core::Atom > &	atoms,
		const ShellTable &	shells,
		const Mat3 &	lattice_bohr,
		double	total_charge
	)

enumerate_g_vectors()

std::vector< Vec3 > occ::xtb::enumerate_g_vectors	(	const Mat3 &	reciprocal_bohr,
		double	recip_cutoff
	)

ewald_real_cutoff()

double occ::xtb::ewald_real_cutoff	(	double	alpha,
		double	tol
	)

ewald_recip_cutoff()

double occ::xtb::ewald_recip_cutoff	(	double	alpha,
		double	tol
	)

fermi_filling()

OrbitalFilling occ::xtb::fermi_filling	(	double	n_electrons,
		double	kt,
		const Vec &	orbital_energies
	)

Fill n_electrons into one spin channel by Fermi-Dirac smearing at electronic temperature kt (this is kB·T in Hartree, not T in Kelvin).

kt <= 0, or a full set of orbitals, falls back to aufbau filling — which is also where any gapped system lands, since at the default 300 K kT ≈ 1 mHa leaves occupations integral to machine precision.

gfn_coordination_numbers()

Vec occ::xtb::gfn_coordination_numbers

(

const std::vector< core::Atom > &

atoms

)

gfn_coordination_numbers_periodic()

Vec occ::xtb::gfn_coordination_numbers_periodic	(	const std::vector< core::Atom > &	atoms,
		const std::vector< LatticeImage > &	lattice_translations
	)

gfn_coordination_numbers_with_gradient()

CoordinationNumbersWithGradient occ::xtb::gfn_coordination_numbers_with_gradient

(

const std::vector< core::Atom > &

atoms

)

h0_scc_gradient()

Mat3N occ::xtb::h0_scc_gradient	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params,
		const ShellTable &	shells,
		const gto::AOBasis &	basis,
		qm::IntegralEngine &	engine,
		const Mat &	S,
		const Mat &	P,
		const Mat &	W,
		const Vec &	V_shell,
		const Vec &	cn,
		const std::vector< Mat3N > &	dcn,
		const Mat &	P_spin = Mat(),
		const Vec &	v_spin_shell = Vec()
	)

klopman_ohno_gamma()

Mat occ::xtb::klopman_ohno_gamma	(	const std::vector< core::Atom > &	atoms,
		const ShellTable &	shells,
		const Gfn2Parameters &	params
	)

klopman_ohno_gamma_energy_gradient()

Mat3N occ::xtb::klopman_ohno_gamma_energy_gradient	(	const std::vector< core::Atom > &	atoms,
		const ShellTable &	shells,
		const Gfn2Parameters &	params,
		const Mat &	gamma_matrix,
		const Vec &	qsh
	)

monkhorst_pack_grid()

std::vector< KPoint > occ::xtb::monkhorst_pack_grid	(	const Mat3 &	reciprocal_bohr,
		int	n1,
		int	n2,
		int	n3
	)

multipole_radii()

Vec occ::xtb::multipole_radii	(	const std::vector< core::Atom > &	atoms,
		const Vec &	cn,
		const Gfn2Parameters &	params
	)

multipole_radii_with_gradient()

MultipoleRadiiWithGradient occ::xtb::multipole_radii_with_gradient	(	const std::vector< core::Atom > &	atoms,
		const Vec &	cn,
		const Gfn2Parameters &	params
	)

periodic_h0_blocks()

std::vector< Mat > occ::xtb::periodic_h0_blocks	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const std::vector< LatticeImage > &	translations,
		const std::vector< Mat > &	S_per_T,
		const Vec &	cn
	)

periodic_klopman_ohno_gamma()

Mat occ::xtb::periodic_klopman_ohno_gamma	(	const PeriodicSystem &	sys,
		const ShellTable &	shells,
		const Gfn2Parameters &	params,
		const EwaldGammaData &	ewald
	)

periodic_klopman_ohno_gamma_direct()

Mat occ::xtb::periodic_klopman_ohno_gamma_direct	(	const PeriodicSystem &	sys,
		const ShellTable &	shells,
		const Gfn2Parameters &	params,
		double	cutoff_bohr
	)

periodic_overlap_blocks()

std::vector< Mat > occ::xtb::periodic_overlap_blocks	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const std::vector< LatticeImage > &	translations
	)

quadrupole_ao_grad()

QuadrupoleGradAO occ::xtb::quadrupole_ao_grad

(

qm::IntegralEngine &

engine

)

quadrupole_ao_matrices()

std::array< Mat, 6 > occ::xtb::quadrupole_ao_matrices	(	qm::IntegralEngine &	engine,
		const Vec3 &	origin = Vec3::Zero()
	)

repulsion_energy()

double occ::xtb::repulsion_energy	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params
	)

repulsion_energy_and_gradient()

RepulsionEnergyGradient occ::xtb::repulsion_energy_and_gradient	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params
	)

repulsion_energy_periodic()

double occ::xtb::repulsion_energy_periodic	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params,
		const std::vector< LatticeImage > &	translations
	)

run_charge_only_periodic_scc()

PeriodicSccResult occ::xtb::run_charge_only_periodic_scc	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const PeriodicSccOptions &	opts = {}
	)

run_charge_only_scc()

SccResult occ::xtb::run_charge_only_scc	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params,
		const SccOptions &	opts = {}
	)

run_gfn2_scc()

SccResult occ::xtb::run_gfn2_scc	(	const std::vector< core::Atom > &	atoms,
		const Gfn2Parameters &	params,
		const SccOptions &	opts = {}
	)

run_periodic_scc_kpoints()

PeriodicSccResult occ::xtb::run_periodic_scc_kpoints	(	const PeriodicSystem &	sys,
		const Gfn2Parameters &	params,
		const std::vector< struct KPoint > &	kpoints,
		const PeriodicSccOptions &	opts = {}
	)

slater_to_gauss()

StoNgFit occ::xtb::slater_to_gauss	(	int	ng,
		int	n,
		int	l,
		double	zeta,
		bool	normalize = true
	)

solve_generalized_hermitian()

CGenSolveResult occ::xtb::solve_generalized_hermitian	(	const CMat &	H,
		const CMat &	S,
		double	s_eps = 1e-10
	)

spin_coupling_matrix()

Mat occ::xtb::spin_coupling_matrix	(	const std::vector< core::Atom > &	atoms,
		const ShellTable &	shells,
		const Gfn2Parameters &	params,
		double	scale = 1.0
	)

On-site spin-coupling matrix W (n_shells × n_shells, Hartree), block diagonal by atom — the GFN-xTB spin interaction has no inter-atomic part.

Given shell magnetizations m (Mulliken pop(α) − pop(β)), the spin energy is E_spin = ½ mᵀWm and the conjugate shell potential is v = Wm. The constants are negative, so polarizing the spin density lowers the energy.

scale multiplies every entry; 0 disables spin polarization, recovering the common-Fock open-shell treatment of plain xtb --uhf. Any other value requires a spin_constants block for every element in the parameter set, and throws naming the element if one is missing.

spin_pair_index()

constexpr int occ::xtb::spin_pair_index ( int  l_i, int  l_j  )

constexpr

tblite_version()

std::string occ::xtb::tblite_version

(

)