"""BIPOLE-style periodic UKS driver in CRYSTAL's electrostatic gauge.
The open-shell DFT counterpart of :mod:`vibeqc.pbc_bipole_rks`.
Uses the same CRYSTAL-gauge Ewald J-split F^2e build for the Hartree
term and adds the spin-polarised libxc XC potential on the periodic
Becke grid. For hybrid functionals a fraction of HF exchange is
retained per spin channel via the native ``build_jk_2e_real_space``.
This driver keeps the same multi-k SCF scaffold as the UHF BIPOLE
driver: shared Ewald a across V_ne/E_nn/J^LR, analytic V_ne via
AO-pair Fourier transforms, real-space energy accounting, and
the maintained convergence accelerators (DIIS, MOM, level-shift schedule,
damping). The historical ODA hook fails closed.
"""
from __future__ import annotations
import warnings
from dataclasses import dataclass, field
from typing import List, Optional, Sequence, Tuple, Union
import numpy as np
from ._vibeqc_core import (
apply_level_shift_k,
BasisSet,
BlochKMesh,
EwaldOptions,
Functional,
GridOptions,
InitialGuess,
LatticeMatrixSet,
LatticeSumOptions,
LevelShiftDensity,
PeriodicKSOptions,
PeriodicSystem,
SCFIteration,
bloch_sum,
build_grid,
build_xc_periodic_uks,
direct_lattice_cells,
ewald_nuclear_repulsion,
nuclear_repulsion_per_cell,
real_space_density_from_kpoints_fractional,
)
from .bipole_ext_el_pole import compute_ext_el_spheropole
from .guess import initial_densities_open_shell, initial_density_closed_shell
from .level_shift_schedule import LevelShiftSchedule
from .mom import select_occupied_by_max_overlap as _mom_select
from .oda import compute_oda_lambda as _compute_oda_lambda
from .oda import oda_mix_densities as _oda_mix
from .pbc_bipole_common import (
bipole_final_density_phase,
unrestricted_occupations_per_spin,
unrestricted_spin_density,
unrestricted_split_k_density_list,
PBCBipoleEnergyComponents,
_bloch_sum_blocks,
_bloch_sum_blocks_multi_k,
_combine_density_sets,
_compute_nuclear_lattice_ewald_reciprocal_ft,
_copy_lattice_with_blocks, # noqa: F401 (compat re-export, see tests/test_pbc_bipole_common.py)
_crystal_ewald_options,
_density_set_gamma_or_lattice,
_emit_bipole_semantic_diagnostic,
_expand_ibz_kmesh_for_ewald_j,
_lattice_contract,
_spin_occupations,
_zero_cross_cell_density,
bvk_torus_density_matrices,
build_bipole_one_electron_lattice,
prepare_bipole_lattice_options,
raise_bipole_ewald_real_cutoff,
reject_bipole_ecp_options,
reject_bipole_fractional_legacy_gauge,
reject_bipole_quartet_far_field,
reject_bipole_lone_non_gamma_kpoint,
reject_bipole_solver_options,
reject_bipole_unsupported_ks_functional,
unrestricted_bipole_commutator_norm,
refresh_bipole_terminal_trace,
resolve_fock_mixing,
resolve_auto_fock_mixing,
resolve_bipole_sr_image_extent,
resolve_bipole_fock_symmetry,
warn_bipole_charged_cell,
warn_bipole_legacy_multik_gauge,
home_cell_block,
smearing_basin_warning,
)
from .pbc_bipole_fock import (
BipoleFockContext,
BipoleScreenedExchangeExecution,
build_bipole_unrestricted_fock,
)
from .periodic_grid import build_periodic_becke_grid
from .periodic_rhf_multi_k_ewald import (
_canonical_orthogonalizer_complex,
_damp_lattice_matrix,
_diag_in_orth_basis,
)
from .periodic_scf_accelerators import (
DynamicDamping,
MultiKPeriodicUHFAccelerator,
)
from .periodic_screened_exchange import resolve_periodic_exchange
from .progress import ProgressLogger, resolve_progress
from .scf_divergence import check_scf_divergence
from .smearing import (
SmearingOptions,
)
from .smearing import (
closed_shell_periodic_occupations as _closed_shell_periodic_occupations,
)
__all__ = [
"PBCBipoleUKSResult",
"run_pbc_bipole_uks",
]
[docs]
@dataclass
class PBCBipoleUKSResult:
"""Result of :func:`run_pbc_bipole_uks`."""
energy: float
e_electronic: float
e_nuclear: float
e_xc: float
e_coulomb: float
e_hf_exchange: float
n_iter: int
converged: bool
s_squared: float
s_squared_ideal: float
mo_energies_alpha: List[np.ndarray]
mo_coeffs_alpha: List[np.ndarray]
fock_alpha: List[np.ndarray]
density_alpha: LatticeMatrixSet
mo_energies_beta: List[np.ndarray]
mo_coeffs_beta: List[np.ndarray]
fock_beta: List[np.ndarray]
density_beta: LatticeMatrixSet
overlap: List[np.ndarray]
hcore: List[np.ndarray]
runtime_backend: str = "pbc-bipole"
scf_trace: List[SCFIteration] = field(default_factory=list)
e_ext_el_spheropole: Optional[float] = None
ewald_alpha_bohr_inv: Optional[float] = None
# Absolute internal ket-image radius used by an erfc SR build, if any.
# The analytic-gradient preview uses this to reject domain mismatch.
sr_image_extent_bohr: Optional[float] = None
# True when the Fock build used the group-invariant pair-resolved domain.
pair_resolved_fock_domain: bool = False
# Dudarev DFT+U contribution per unit cell (Hartree). 0 unless the
# caller passed ``dft_plus_u=[HubbardSite(...)]``. Sum of per-spin
# contributions for the open-shell UKS path.
e_dft_plus_u: float = 0.0
energy_components: List[PBCBipoleEnergyComponents] = field(
default_factory=list,
)
# Gauge provenance (option (b)): see run_pbc_bipole_uhf.
exchange_ewald_split: bool = False
exchange_exxdiv: Optional[str] = None
# Non-None when finite-T smearing straddled the HOMO-LUMO gap and may
# have selected a near-metallic basin (ionic-Γ basin trap).
basin_warning: Optional[str] = None
functional: str = ""
# Smearing diagnostics (zero when smearing_temperature == 0).
smearing_temperature: float = 0.0
fermi_level: float = 0.0
entropy: float = 0.0
free_energy: float = 0.0
occupations_alpha: List[np.ndarray] = field(default_factory=list)
occupations_beta: List[np.ndarray] = field(default_factory=list)
# Cartesian k-points (bohr^-1) and weights this result spans, in the
# same order as the per-k, per-spin ``mo_coeffs_*`` / ``mo_energies_*``
# lists. Lets optional single-k output writers locate Gamma instead of
# assuming the first k-point is Gamma. See PBCBipoleRHFResult.
kpoints_cart: Optional[np.ndarray] = None
kpoint_weights: Optional[np.ndarray] = None
# Effective previous-Fock weight after the shared automatic default is
# resolved. This can differ from ``options.fock_mixing``.
fock_mixing: float = 0.0
screened_exchange_execution: Optional[
BipoleScreenedExchangeExecution
] = None
# Corrected-gauge overlap-fold convergence diagnostic. Appended to
# preserve the positional signature of the historical result fields.
overlap_fold_drift: Optional[float] = None
# BIPOLE-EXACT-ZONE increment 1b: radius (bohr) of the exact erfc
# output zone when restricted below the operator cutoff (None =
# exact zone == cutoff). Analytic-gradient consumers fail closed.
exact_zone_bohr: Optional[float] = None
# Fixed-Nalpha/Nbeta smearing solves one chemical potential per spin.
# Appended to preserve positional compatibility; ``fermi_level`` remains
# the historical singular alias.
fermi_level_alpha: Optional[float] = None
fermi_level_beta: Optional[float] = None
@dataclass
class _PBCBipoleUKSFockBuild:
"""Internal Fock bundle for one UKS density pair."""
f2e_alpha_real: LatticeMatrixSet
f2e_beta_real: LatticeMatrixSet
f_alpha_k_list: List[np.ndarray]
f_beta_k_list: List[np.ndarray]
e_j_short_range: Optional[float] = None
e_j_long_range: Optional[float] = None
e_exchange: Optional[float] = None
e_j_multipole: Optional[float] = None
# k-space per-spin exchange correction (Ewald exchange split,
# a_HF-scaled); lives in F_s(k) -- caller adds to E_2e.
e_2e_k_correction: float = 0.0
# The q+G=0 (Madelung / exxdiv='ewald') share of e_2e_k_correction on
# its own, so the gauge is visible next to the total (#82).
e_exchange_finite_size: Optional[float] = None
# XC energy of the SAME grid quadrature whose per-spin V_xc entered
# f_alpha/beta_k_list (None for the HF-like PATOM seed build).
# Consuming this instead of re-running build_xc_periodic_uks keeps
# the iteration's V_xc and e_xc from one build.
e_xc: Optional[float] = None
screened_exchange_execution: Optional[
BipoleScreenedExchangeExecution
] = None
[docs]
def run_pbc_bipole_uks(
system: PeriodicSystem,
basis: BasisSet,
kmesh: BlochKMesh,
options=None,
*,
functional: Optional[str] = None,
linear_dep_threshold: float = 1e-7,
fock_mixing: Optional[float] = None,
canonical_orth_normalize_diag_first: bool = True,
level_shift_schedule: Optional[LevelShiftSchedule] = None,
use_mom: bool = False,
use_oda: bool = False,
oda_trust_lambda_max: float = 1.0,
use_incremental_fock: bool = True,
use_ewald_j_split: Optional[bool] = None,
ewald_omega: Optional[float] = None,
ewald_precision: float = 1e-8,
v_ne_grid_options: Optional[GridOptions] = None,
use_multipole_far_field: Optional[bool] = False,
use_exchange_ewald_split: Optional[bool] = None,
exchange_exxdiv: str = "ewald",
multipole_l_max: int = 2,
use_fock_symmetry: Optional[bool] = None,
use_fock_symmetry_reduce: Optional[bool] = None,
sr_image_precision: Optional[float] = 1e-6,
sr_image_extent_bohr: Optional[float] = None,
exact_zone_bohr: Optional[float] = None,
progress: Union[bool, ProgressLogger, None] = None,
verbose: Optional[int] = None,
bz_integration: Optional[str] = None,
init_alpha: Optional[Sequence[np.ndarray]] = None,
init_beta: Optional[Sequence[np.ndarray]] = None,
dft_plus_u: Optional[List["HubbardSite"]] = None,
) -> PBCBipoleUKSResult:
"""Multi-k open-shell UKS via the CRYSTAL-gauge BIPOLE scaffold.
``fock_mixing`` overrides ``options.fock_mixing`` when supplied and is
forwarded through both phases of a spin schedule without rewriting the
caller's options field. A resolved zero can still activate the documented
DIIS-off KS automatic value.
``sr_image_precision`` / ``sr_image_extent_bohr`` and the automatic
``use_fock_symmetry_reduce=None`` policy match
:func:`run_pbc_bipole_rhf`. Spin-schedule recursion forwards all three
controls unchanged.
``bz_integration="gilat"`` applies the T=0 Gilat-Raubenheimer microcell
integral independently to the fixed alpha and beta populations on full
or symmetry-reduced Monkhorst-Pack meshes. It has zero entropy and cannot
be combined with a positive ``options.smearing_temperature``.
``dft_plus_u``: optional list of :class:`HubbardSite`. Same
per-spin per-k convention as :func:`run_pbc_bipole_uhf` --
``F_s(k) += S(k) V_AO_s S(k)`` with
``V_AO_s = U_eff (1/2 - n_s)``; ``E_U_total`` is summed over
spins and surfaced via ``result.e_dft_plus_u``.
"""
reject_bipole_quartet_far_field(
use_multipole_far_field,
driver="run_pbc_bipole_uks",
)
reject_bipole_lone_non_gamma_kpoint(
kmesh,
driver="run_pbc_bipole_uks",
)
from ._vibeqc_core import PeriodicKSOptions as _PKSOpts
opts = options if options is not None else _PKSOpts()
reject_bipole_ecp_options(
opts,
driver="run_pbc_bipole_uks",
basis=basis,
system=system,
)
reject_bipole_solver_options(opts, driver="run_pbc_bipole_uks")
if int(opts.max_iter) < 1:
raise ValueError("run_pbc_bipole_uks: max_iter must be at least 1")
if use_oda:
raise NotImplementedError(
"run_pbc_bipole_uks: unrestricted ODA is unavailable because "
"the current line search does not include the beta-spin energy "
"direction; use DIIS instead"
)
requested_fock_mixing = resolve_fock_mixing(
opts,
fock_mixing,
where="run_pbc_bipole_uks",
)
# SPINLOCK. SPIN_SCHEDULE (two-phase) is delegated before SCF setup;
# PATTERN_HOLD reuses the per-k MOM machinery below (gated to the
# spinlock window).
from ._vibeqc_core import SpinlockMode
from .spinlock_periodic import check_spinlock_support, run_spin_schedule
_initial_guess = getattr(opts, "initial_guess", InitialGuess.HCORE)
_broken_state_symmetry_controls = []
if getattr(opts, "atomic_spins", None):
_broken_state_symmetry_controls.append("atomic_spins")
if bool(use_mom):
_broken_state_symmetry_controls.append("use_mom")
if getattr(opts, "spinlock_mode", SpinlockMode.OFF) != SpinlockMode.OFF:
_broken_state_symmetry_controls.append("spinlock")
if bool(dft_plus_u):
_broken_state_symmetry_controls.append("dft_plus_u")
if init_alpha is not None or init_beta is not None:
_broken_state_symmetry_controls.append("initial spin density")
if _initial_guess in (InitialGuess.READ, InitialGuess.PATOM):
_broken_state_symmetry_controls.append(_initial_guess.name.lower())
if (
bool(use_fock_symmetry) or use_fock_symmetry_reduce is True
) and _broken_state_symmetry_controls:
raise NotImplementedError(
"run_pbc_bipole_uks: explicit Fock symmetry enforcement or "
"reduction cannot be combined with an electronically broken or "
"unverified state control ("
+ ", ".join(_broken_state_symmetry_controls)
+ "). Disable Fock symmetry, or remove the state-selective "
"control and opt in only for a symmetry-covariant density."
)
_spin_schedule_requested = (
getattr(opts, "spinlock_mode", SpinlockMode.OFF) == SpinlockMode.SPIN_SCHEDULE
and int(getattr(opts, "spinlock_iterations", 0)) > 0
)
if _spin_schedule_requested:
_schedule_ir = np.asarray(
getattr(kmesh, "ir_mapping", []), dtype=int
).reshape(-1)
_schedule_true_multik = (
len(list(kmesh.kpoints)) > 1
or _schedule_ir.size > 1
or int(
np.prod(np.asarray(getattr(kmesh, "mesh", (1, 1, 1))))
) > 1
)
if _schedule_true_multik:
raise NotImplementedError(
"run_pbc_bipole_uks: SPIN_SCHEDULE is Gamma-only. Its "
"phase-2 restart currently carries only the home-cell spin "
"densities and cannot reconstruct a complete multi-k state. "
"Use PATTERN_HOLD or a Gamma mesh."
)
return run_spin_schedule(
lambda sysx, o: run_pbc_bipole_uks(
sysx,
basis,
kmesh,
o,
functional=functional,
linear_dep_threshold=linear_dep_threshold,
fock_mixing=requested_fock_mixing,
canonical_orth_normalize_diag_first=canonical_orth_normalize_diag_first,
level_shift_schedule=level_shift_schedule,
use_mom=use_mom,
use_oda=use_oda,
oda_trust_lambda_max=oda_trust_lambda_max,
use_incremental_fock=use_incremental_fock,
use_ewald_j_split=use_ewald_j_split,
ewald_omega=ewald_omega,
ewald_precision=ewald_precision,
v_ne_grid_options=v_ne_grid_options,
use_multipole_far_field=use_multipole_far_field,
use_exchange_ewald_split=use_exchange_ewald_split,
exchange_exxdiv=exchange_exxdiv,
multipole_l_max=multipole_l_max,
use_fock_symmetry=use_fock_symmetry,
use_fock_symmetry_reduce=use_fock_symmetry_reduce,
sr_image_precision=sr_image_precision,
sr_image_extent_bohr=sr_image_extent_bohr,
exact_zone_bohr=exact_zone_bohr,
progress=progress,
verbose=verbose,
bz_integration=bz_integration,
dft_plus_u=dft_plus_u,
),
system,
opts,
)
check_spinlock_support(
opts,
{SpinlockMode.PATTERN_HOLD, SpinlockMode.SPIN_SCHEDULE},
"the BIPOLE UKS driver",
)
if functional is not None:
opts.functional = str(functional)
if not getattr(opts, "functional", None):
opts.functional = "pbe"
smearing_T = float(getattr(opts, "smearing_temperature", 0.0))
if smearing_T < 0.0:
raise ValueError("run_pbc_bipole_uks: smearing_temperature must be >= 0")
if bz_integration is not None:
bz_integration = str(bz_integration).strip().lower()
if bz_integration not in (None, "smearing", "gilat"):
raise ValueError(
"run_pbc_bipole_uks: bz_integration must be None, 'smearing', "
f"or 'gilat'; got {bz_integration!r}"
)
use_gilat = bz_integration == "gilat"
if use_gilat and smearing_T > 0.0:
raise ValueError(
"run_pbc_bipole_uks: bz_integration='gilat' is a T=0 "
"integrator; do not combine it with smearing_temperature > 0"
)
use_fractional_density = (smearing_T > 0.0) or use_gilat
func = Functional(opts.functional, 2) # spin-polarised
reject_bipole_unsupported_ks_functional(
func,
driver="run_pbc_bipole_uks",
)
# CAM exchange assembly (see run_pbc_bipole_rks): alpha_hf is the
# FULL-RANGE arm only; screened hybrids (hse06, c_full = 0) get
# their erfc short-range K inside build_bipole_unrestricted_fock
# (no seam, no far-field); LR-heavy RSH fails closed here.
exx = resolve_periodic_exchange(func, where="run_pbc_bipole_uks")
alpha_hf = float(exx.c_full)
# CRYSTAL-style auto-FMIXING: fires only for DFT without DIIS.
# Validated on the closed-shell twin (RKS Gap-B run matrix,
# 2026-07-13); the shared Fock builder makes the damping behaviour
# spin-independent. See resolve_auto_fock_mixing.
fock_mixing_value = resolve_auto_fock_mixing(
requested_fock_mixing,
alpha_hf=alpha_hf,
use_diis=bool(opts.use_diis),
where="run_pbc_bipole_uks",
)
lat_opts: LatticeSumOptions = opts.lattice_opts
plog = resolve_progress(progress, verbose=verbose)
(
use_ewald_j_split,
use_ewald_j_split_auto,
lat_opts_2e,
lat_opts_1e,
) = prepare_bipole_lattice_options(system, lat_opts, use_ewald_j_split, plog)
n_elec = int(system.n_electrons())
n_alpha, n_beta = _spin_occupations(system)
# ``_spin_occupations`` promotes the default multiplicity on an odd-
# electron periodic cell to the minimum valid open shell without mutating
# the caller's system. Report the multiplicity of that executed state.
mult = int(n_alpha - n_beta + 1)
# Open-shell guard moved after auto-disable resolution below.
plog.info(
f"PBC BIPOLE UKS (CRYSTAL-gauge) / cutoff {lat_opts.cutoff_bohr:.2f} bohr"
)
if exx.is_screened:
plog.info(
f" functional = {opts.functional}, screened exchange "
f"K = {exx.c_sr:g}*K_erfc(omega={exx.omega_screen:g} bohr^-1)"
)
else:
plog.info(
f" functional = {opts.functional}, hf_exchange_fraction = {alpha_hf}"
)
plog.info(f" n_alpha = {n_alpha}, n_beta = {n_beta}, multiplicity = {mult}")
_kmesh_ibz = kmesh
_ir_mapping = np.asarray(getattr(kmesh, "ir_mapping", []), dtype=int).reshape(-1)
k_points = list(_kmesh_ibz.kpoints)
weights = np.asarray(_kmesh_ibz.weights, dtype=float)
_input_true_multik = (
len(k_points) > 1
or _ir_mapping.size > 1
or int(np.prod(np.asarray(getattr(kmesh, "mesh", (1, 1, 1))))) > 1
)
if use_ewald_j_split and _ir_mapping.size > 0:
# IBZ inputs run on the EXPANDED full mesh (correctness: the
# IBZ-native replication shortcut lacked the star AO rotations
# D(R.k) = P(R).D(k).P(R)ᵀ and broke non-trivial crystals -- MgO
# probe 2026-06-10, 8.25 Ha. See vibeqc.periodic_k_symmetry for
# the transport groundwork and pbc_bipole.py for the full note).
kmesh_full = _expand_ibz_kmesh_for_ewald_j(system, kmesh, plog)
if len(list(kmesh_full.kpoints)) > len(k_points):
kmesh = kmesh_full
k_points = list(kmesh.kpoints)
weights = np.asarray(kmesh.weights, dtype=float)
_ir_mapping = np.asarray([], dtype=int)
k_points_full = k_points
weights_full = weights
else:
k_points_full = k_points
weights_full = weights
n_k = len(k_points)
if n_k == 0:
raise ValueError("kmesh has no k-points")
if not np.isclose(weights.sum(), 1.0):
raise ValueError(f"kmesh.weights must sum to 1; got {weights.sum():.6f}")
if (
_input_true_multik
and init_alpha is None
and init_beta is None
and getattr(opts, "initial_guess", InitialGuess.HCORE) == InitialGuess.READ
):
raise NotImplementedError(
"run_pbc_bipole_uks: multi-k READ requires explicit complete "
"real-space init_alpha/init_beta block sets; Gamma-only read "
"densities cannot reconstruct the per-k state."
)
if use_ewald_j_split and n_k > 1 and _ir_mapping.size == 0:
uniform_w = 1.0 / float(n_k)
if not np.allclose(weights, uniform_w, atol=1e-9):
raise ValueError(
"use_ewald_j_split at multi-k requires uniform weights or IBZ mesh"
)
plog.info(f"k-mesh: {n_k} k-points, weights sum = {weights.sum():.4f}")
# ---- Exchange/gauge resolution (option (b) Phase 4b, 2026-06-11) --
# Mirrors run_pbc_bipole_uhf: per-spin exchange split at 3D Γ,
# alpha_HF-scaled for hybrids; pure functionals get the gauge change
# only (no exchange machinery).
if exchange_exxdiv not in ("ewald", "none"):
raise ValueError(
f"run_pbc_bipole_uks: exchange_exxdiv must be 'ewald' or "
f"'none'; got {exchange_exxdiv!r}"
)
_x_split_auto = use_exchange_ewald_split is None
exchange_split_active = (
bool(use_ewald_j_split) if _x_split_auto else bool(use_exchange_ewald_split)
)
if exchange_split_active and not use_ewald_j_split:
raise ValueError(
"run_pbc_bipole_uks: use_exchange_ewald_split=True requires "
"the Ewald J split (use_ewald_j_split=True)."
)
# Multi-k split (option (b) Phase 3): needs the true Monkhorst-
# Pack dimensions (q-channel tables, BvK-torus fold, supercell
# Madelung); ad-hoc k-lists are rejected.
_bvk_mesh: Optional[Tuple[int, int, int]] = None
if exchange_split_active and n_k > 1:
_mesh_attr = tuple(int(x) for x in getattr(kmesh, "mesh", (1, 1, 1)))
if int(np.prod(_mesh_attr)) != n_k:
if _x_split_auto:
plog.info(
" multi-k corrected exchange gauge needs a "
"Monkhorst-Pack mesh (BvK-torus fold + supercell ξ_M); "
"this ad-hoc k-list has no mesh metadata -> falling back "
"to the legacy gauge. Pass a monkhorst_pack(...) mesh "
"for the corrected gauge."
)
exchange_split_active = False
else:
raise ValueError(
"run_pbc_bipole_uks: the Ewald exchange split at multi-k "
"requires a Monkhorst-Pack BlochKMesh carrying its mesh "
f"dimensions (got mesh={_mesh_attr} for {n_k} k-points). "
"Build the mesh via monkhorst_pack(...); ad-hoc k-point "
"lists are not supported on the corrected gauge."
)
else:
_bvk_mesh = _mesh_attr
reject_bipole_fractional_legacy_gauge(
use_ewald_j_split=bool(use_ewald_j_split),
exchange_split_active=exchange_split_active,
fractional_occupations=use_fractional_density,
driver="run_pbc_bipole_uks",
)
_ff_enable: Optional[bool] = False
warn_bipole_legacy_multik_gauge(system, exchange_split_active, n_k, plog)
warn_bipole_charged_cell(system, plog)
_xi_madelung = 0.0
if exchange_split_active and exchange_exxdiv == "ewald" and alpha_hf > 0.0:
if n_k > 1:
from .bipole_fock_ewald import probe_charge_madelung_supercell
assert _bvk_mesh is not None
_xi_madelung = probe_charge_madelung_supercell(system, _bvk_mesh)
else:
from .bipole_fock_ewald import probe_charge_madelung
_xi_madelung = probe_charge_madelung(system)
overlap_fold_drift: Optional[float] = None
if exchange_split_active:
plog.info(
" Gauge: corrected (full Bloch density, no spheropole"
+ (
f"; per-spin exchange split exxdiv={exchange_exxdiv}, "
f"alpha_HF={alpha_hf:g}"
if alpha_hf > 0.0
else "; pure functional"
)
+ ")"
)
# Shared Ewald state
ewald_options_1e = None
omega_used = None
ewald_cell_volume = None
ewald_k_max: Optional[float] = None
if system.dim == 3:
from .bipole_ext_el_pole import (
crystal_default_ewald_alpha,
crystal_ewald_reciprocal_cutoff,
)
V_cell = float(abs(np.linalg.det(np.asarray(system.lattice, dtype=float))))
ewald_cell_volume = V_cell
omega_used = (
float(ewald_omega)
if ewald_omega is not None
else crystal_default_ewald_alpha(V_cell)
)
ewald_k_max = crystal_ewald_reciprocal_cutoff(V_cell)
# #478: the pinned alpha = 2.8/V^(1/3) makes erfc(alpha.R) at the
# nearest image an L-INDEPENDENT 7.5e-5, so the 1e nuclear/Ewald
# real-space sum must be sized from alpha, not from the AO cutoff.
raise_bipole_ewald_real_cutoff(
system,
lat_opts_1e,
omega_used,
float(ewald_precision),
plog,
)
ewald_options_1e = _crystal_ewald_options(
lat_opts_1e,
alpha_bohr_inv=omega_used,
tolerance=float(ewald_precision),
recip_cutoff_bohr_inv=ewald_k_max,
)
# Match the restricted driver: one padded ket-image ball converges the
# Ewald J and screened-exchange erfc kernels, so the smaller omega owns
# the radius.
_sr_domain_omega = (
min(float(omega_used), float(exx.omega_screen))
if exx.is_screened and omega_used is not None
else omega_used
)
_sr_image_extent = resolve_bipole_sr_image_extent(
basis,
system,
lat_opts,
lat_opts_2e,
_sr_domain_omega,
use_ewald_j_split=bool(use_ewald_j_split),
sr_image_precision=sr_image_precision,
sr_image_extent_bohr=sr_image_extent_bohr,
plog=plog,
)
# DFT grid
if getattr(opts, "use_periodic_becke", False):
grid = build_periodic_becke_grid(
system,
grid_options=opts.grid,
image_radius_bohr=float(getattr(opts, "becke_image_radius_bohr", 10.0)),
)
else:
grid = build_grid(system.unit_cell_molecule(), opts.grid)
# One-electron integrals
with plog.stage(
"integrals_lattice", detail=f"S/T/V at cutoff {lat_opts.cutoff_bohr:.2f} bohr"
):
S_lat, T_lat, V_lat, v_ne_lr_cache = build_bipole_one_electron_lattice(
basis,
system,
lat_opts_1e,
lat_opts_2e,
ewald_options_1e,
ewald_precision,
ewald_k_max,
v_ne_grid_options,
plog,
sym_log_style="rich",
)
cells = list(S_lat.cells)
# SYM3b Fock-symmetry resolution -- before the density-list decision
# (pair-resolved mode widens the density support; see
# run_pbc_bipole_rhf).
# A requested exact zone is not composable with the SYM3b reduced /
# pair-resolved output domains yet (increment 1): let an AUTO
# reduction yield to the explicit zone request; an explicit
# use_fock_symmetry_reduce=True still reaches the resolver's
# fail-closed raise below.
_reduce_request = use_fock_symmetry_reduce
if exact_zone_bohr is not None and _reduce_request is None:
_reduce_request = False
_fock_sym_map, _rep_cell_indices = resolve_bipole_fock_symmetry(
system,
basis,
lat_opts_2e,
use_fock_symmetry,
_reduce_request,
plog,
per_spin=True,
exchange_split_active=exchange_split_active,
# Structural symmetry alone does not prove that an unrestricted
# electronic state is symmetry-covariant. Keep AUTO off for UKS;
# explicit reduction remains an opt-in after the guard above.
auto_reduce_safe=False,
)
_pair_mode = _fock_sym_map is not None and getattr(
_fock_sym_map, "pair_resolved", False
)
from .pbc_bipole_common import resolve_bipole_exact_zone
_exact_zone = resolve_bipole_exact_zone(
system,
lat_opts_2e,
exact_zone_bohr,
exchange_split_active=exchange_split_active,
sr_image_extent=_sr_image_extent,
pair_mode=_pair_mode,
rep_cell_indices=_rep_cell_indices,
plog=plog,
)
# ---- Lattice-fold convergence guard (gauge-independent) -------------
# Shared guard (enforce_bipole_fold_support); hoisted above the gauge
# condition 2026-08-06. The wide density list below remains
# corrected-gauge-only.
from .pbc_bipole_common import enforce_bipole_fold_support
overlap_fold_drift = enforce_bipole_fold_support(
basis,
system,
lat_opts_2e,
method="uks",
n_k=n_k,
k_points=(k_points if n_k > 1 else None),
exchange_split_active=exchange_split_active,
plog=plog,
)
if exchange_split_active:
if _pair_mode:
# M3: pair-resolved density support (see run_pbc_bipole_rhf).
cells_density = list(_fock_sym_map.density_domain.cells)
plog.info(
f" density cell list: {len(cells_density)} cells "
f"(pair-resolved support at 2x cutoff; SR-masked privately)"
)
else:
cells_density = list(
direct_lattice_cells(
system, 2.0 * float(lat_opts_2e.cutoff_bohr)
)
)
plog.info(
f" density cell list: {len(cells_density)} cells (2x cutoff)"
)
else:
cells_density = cells
# Per-k matrices
from .linear_dependence import scf_preflight_overlap_check
S_k_list = []
Hcore_k_list = []
X_k_list = []
for k_idx, k in enumerate(k_points):
k_arr = np.asarray(k, dtype=float).reshape(3)
S_k = np.asarray(bloch_sum(S_lat, k_arr))
T_k = np.asarray(bloch_sum(T_lat, k_arr))
V_k = np.asarray(bloch_sum(V_lat, k_arr))
H_k = T_k + V_k
S_k = 0.5 * (S_k + S_k.conj().T)
H_k = 0.5 * (H_k + H_k.conj().T)
scf_preflight_overlap_check(S_k, plog=plog, label=f"S(k={k_idx})", basis=basis)
X_k, n_kept = _canonical_orthogonalizer_complex(
S_k,
linear_dep_threshold,
normalize_diag_first=canonical_orth_normalize_diag_first,
)
if max(n_alpha, n_beta) > n_kept:
raise RuntimeError(
f"run_pbc_bipole_uks: canonical orth at k={k_idx} dropped too many directions"
)
S_k_list.append(S_k)
Hcore_k_list.append(H_k)
X_k_list.append(X_k)
# Nuclear repulsion
e_nuc = (
float(ewald_nuclear_repulsion(system, ewald_options_1e))
if ewald_options_1e is not None
else float(nuclear_repulsion_per_cell(system, lat_opts_1e))
)
# Initial guess
C_alpha_per_k = []
eps_alpha_per_k = []
C_beta_per_k = []
eps_beta_per_k = []
for H_k, X_k in zip(Hcore_k_list, X_k_list):
C_a, eps_a = _diag_in_orth_basis(H_k, X_k)
C_b, eps_b = _diag_in_orth_basis(H_k, X_k)
C_alpha_per_k.append(C_a.astype(complex))
eps_alpha_per_k.append(eps_a)
C_beta_per_k.append(C_b.astype(complex))
eps_beta_per_k.append(eps_b)
def _spin_density(C_per_k_local, n_occ_each):
return unrestricted_spin_density(
C_per_k_local,
n_occ_each,
n_k=n_k,
kmesh=kmesh,
cells_density=cells_density,
exchange_split_active=exchange_split_active,
)
D_alpha_real = _spin_density(C_alpha_per_k, n_alpha)
D_beta_real = _spin_density(C_beta_per_k, n_beta)
# --- Smearing occupation helpers (open-shell: per-spin mu) ---
from .smearing.fermi_dirac import fermi_dirac_occupations_per_k as _fd_per_k
def _occupations_per_spin(eps_spin_per_k, n_spin):
return unrestricted_occupations_per_spin(
eps_spin_per_k,
n_spin,
smearing_T=smearing_T,
weights=weights,
system=system,
kmesh=kmesh,
bz_integration=bz_integration,
)
occ_alpha_per_k, mu_alpha, entropy_alpha = _occupations_per_spin(
eps_alpha_per_k, n_alpha
)
occ_beta_per_k, mu_beta, entropy_beta = _occupations_per_spin(
eps_beta_per_k, n_beta
)
entropy = entropy_alpha + entropy_beta
if use_fractional_density:
D_alpha_real = real_space_density_from_kpoints_fractional(
C_alpha_per_k, occ_alpha_per_k, kmesh, cells_density
)
D_beta_real = real_space_density_from_kpoints_fractional(
C_beta_per_k, occ_beta_per_k, kmesh, cells_density
)
if not exchange_split_active:
_zero_cross_cell_density(D_alpha_real, D_alpha_real.blocks[0].shape[0], n_k)
_zero_cross_cell_density(D_beta_real, D_beta_real.blocks[0].shape[0], n_k)
# Caller-supplied warm-start spin densities take precedence over
# the SAD/Hcore guess engine -- see run_pbc_bipole_uhf for the
# same contract. Used by the NEB driver for within-image density
# warm-start for periodic NEB.
if (init_alpha is not None) != (init_beta is not None):
raise ValueError(
"run_pbc_bipole_uks: init_alpha and init_beta must be "
"provided together (both None or both populated)"
)
if init_alpha is not None and init_beta is not None:
blocks_a = list(init_alpha)
blocks_b = list(init_beta)
if len(blocks_a) != len(D_alpha_real.cells):
raise ValueError(
f"run_pbc_bipole_uks: init_alpha has {len(blocks_a)} "
f"blocks; expected {len(D_alpha_real.cells)}"
)
if len(blocks_b) != len(D_beta_real.cells):
raise ValueError(
f"run_pbc_bipole_uks: init_beta has {len(blocks_b)} "
f"blocks; expected {len(D_beta_real.cells)}"
)
for g_idx, (ba, bb) in enumerate(zip(blocks_a, blocks_b)):
D_alpha_real.set_block(g_idx, np.asarray(ba, dtype=float))
D_beta_real.set_block(g_idx, np.asarray(bb, dtype=float))
initial_density_is_local = True
density_from_c_per_k = False
else:
guess = getattr(opts, "initial_guess", InitialGuess.HCORE)
# ATOMSPIN: see pbc_bipole_uhf -- when a per-atom spin pattern is
# requested it must reach the open-shell engine, not the even-electron
# closed-shell shortcut (which would wash it out to a 50/50 split).
_atomic_spins = getattr(opts, "atomic_spins", None) or None
# READ carries the prior's per-spin g=0 densities -- skip the
# even-electron 50/50 shortcut for READ too (see pbc_bipole_uhf).
_is_read = guess == InitialGuess.READ
_needs_open_context = guess in {
InitialGuess.SAP,
InitialGuess.PATOM,
InitialGuess.HUECKEL,
InitialGuess.MINAO,
}
_patom_seed_pending = guess == InitialGuess.PATOM
D_guess = None
if (
n_elec % 2 == 0
and _atomic_spins is None
and not _is_read
and not _needs_open_context
):
D_total_guess = initial_density_closed_shell(
system.unit_cell_molecule(), basis, n_elec // 2, guess, is_periodic=True
)
if D_total_guess is not None:
D_guess = (
0.5 * np.asarray(D_total_guess, dtype=float),
0.5 * np.asarray(D_total_guess, dtype=float),
)
if D_guess is None:
_seed_guess = InitialGuess.SAD if _patom_seed_pending else guess
D_guess = initial_densities_open_shell(
system.unit_cell_molecule(),
basis,
n_alpha,
n_beta,
_seed_guess,
is_periodic=True,
periodic_system=system,
lattice_opts=lat_opts,
atomic_spins=_atomic_spins,
read_density_alpha=getattr(opts, "read_density_alpha", None),
read_density_beta=getattr(opts, "read_density_beta", None),
read_path=getattr(opts, "read_path", ""),
)
initial_density_is_local = D_guess is not None
if D_guess is not None:
D_a0, D_b0 = D_guess
# Multi-k must start from one internally consistent Bloch fold.
# Mixing GuessEngine g=0 with Hcore g!=0 is non-idempotent and
# produces the same iteration-2 Fock overshoot already diagnosed
# in the RKS implementation. Keep the full per-k Hcore fold for
# ordinary SAD/SAP/etc. Deliberately local ATOMSPIN and PATOM
# seeds remain
# installed at g=0 with zero cross-cell blocks: ATOMSPIN preserves
# the requested broken symmetry, while PATOM must feed its SAD
# seed into the one in-field Fock step below. A per-k projected
# form of either seed is not implemented yet.
if n_k > 1:
if _atomic_spins is None and not _patom_seed_pending:
plog.info(
f"initial guess: {guess.name} (multi-k: retaining "
"the complete per-k Hcore fold for consistent "
"cross-cell XC density)"
)
initial_density_is_local = False
else:
seed_label = (
"PATOM SAD"
if _patom_seed_pending
else "ATOMSPIN"
)
plog.info(
f"initial guess: {guess.name} (multi-k {seed_label}: "
"local g=0 seed)"
)
zero_a = np.zeros_like(D_a0, dtype=float)
zero_b = np.zeros_like(D_b0, dtype=float)
for g_idx in range(len(D_alpha_real.cells)):
is_g0 = (
np.asarray(
D_alpha_real.cells[g_idx].index, dtype=int
)
== np.array([0, 0, 0])
).all()
D_alpha_real.set_block(
g_idx, D_a0 if is_g0 else zero_a
)
D_beta_real.set_block(
g_idx, D_b0 if is_g0 else zero_b
)
else:
zero_a = np.zeros_like(D_a0, dtype=float)
zero_b = np.zeros_like(D_b0, dtype=float)
for g_idx in range(len(D_alpha_real.cells)):
is_g0 = (
np.asarray(D_alpha_real.cells[g_idx].index, dtype=int)
== np.array([0, 0, 0])
).all()
D_alpha_real.set_block(g_idx, D_a0 if is_g0 else zero_a)
D_beta_real.set_block(g_idx, D_b0 if is_g0 else zero_b)
density_from_c_per_k = not initial_density_is_local
if init_alpha is not None and init_beta is not None:
_patom_seed_pending = False
D_alpha_prev = None
D_beta_prev = None
# SCF aids
damping = float(opts.damping)
if not (0.0 <= damping < 1.0):
raise ValueError(
f"run_pbc_bipole_uks: damping must be in [0,1); got {damping}"
)
damper: Optional[DynamicDamping] = None
if bool(getattr(opts, "dynamic_damping", False)):
damper = DynamicDamping(
initial_alpha=damping,
alpha_min=float(getattr(opts, "dynamic_damping_min", 0.0)),
alpha_max=float(getattr(opts, "dynamic_damping_max", 0.95)),
)
use_diis = bool(opts.use_diis)
diis_start_iter = int(opts.diis_start_iter)
accel: Optional[MultiKPeriodicUHFAccelerator] = (
MultiKPeriodicUHFAccelerator(opts) if use_diis else None
)
level_shift_static = float(getattr(opts, "level_shift", 0.0))
if level_shift_schedule is not None and not isinstance(
level_shift_schedule, LevelShiftSchedule
):
raise TypeError(f"level_shift_schedule must be LevelShiftSchedule")
# CRYSTAL-style FMIXING (per-spin, per-k).
# Value resolved above in the options setup; log it here near the
# SCF-loop preamble.
if fock_mixing_value != 0.0:
plog.info(
f"fock mixing: CRYSTAL FMIXING "
f"{100.0 * fock_mixing_value:.1f}% "
"(previous Fock matrix weight)"
)
F_alpha_prev_mixed: Optional[List[np.ndarray]] = None
F_beta_prev_mixed: Optional[List[np.ndarray]] = None
# SPINLOCK PATTERN_HOLD reuses the per-k MOM machinery (gated to cycles
# 2..spinlock_iterations) to hold the seeded broken-symmetry occupied set
# then release -- protecting an ATOMSPIN seed.
_spinlock_pattern_hold = (
getattr(opts, "spinlock_mode", SpinlockMode.OFF) == SpinlockMode.PATTERN_HOLD
and int(getattr(opts, "spinlock_iterations", 0)) > 0
)
_spinlock_iters = int(getattr(opts, "spinlock_iterations", 0))
if use_mom:
plog.info("MOM: ON")
elif _spinlock_pattern_hold:
plog.info(f"SPINLOCK PATTERN_HOLD: MOM-hold for {_spinlock_iters} cycles")
C_prev_occ_alpha_per_k = None
C_prev_occ_beta_per_k = None
if use_oda and use_diis:
raise ValueError("use_oda and use_diis are mutually exclusive")
if use_oda:
plog.info(f"ODA: ON (trust lambda_max = {oda_trust_lambda_max})")
# Ewald J-split cache
j_lr_cache = v_ne_lr_cache
if use_ewald_j_split:
if system.dim != 3:
raise ValueError(f"use_ewald_j_split requires dim=3")
from .bipole_fock_ewald import _build_j_long_range_cache
assert omega_used is not None
if _pair_mode:
# M3: J^LR blocks on the pair-resolved output template
# (dedicated cache; never the radial V_ne one).
j_lr_cache = _build_j_long_range_cache(
basis,
system,
np.array(
[
np.asarray(c.r_cart, dtype=float)
for c in _fock_sym_map.cells
],
dtype=float,
),
omega_used,
ewald_precision,
K_max=ewald_k_max,
)
elif j_lr_cache is None:
cells_r_cart_arr = np.array(
[np.asarray(c.r_cart, dtype=float) for c in cells], dtype=float
)
j_lr_cache = _build_j_long_range_cache(
basis,
system,
cells_r_cart_arr,
omega_used,
ewald_precision,
K_max=ewald_k_max,
)
# Multi-k split: per-(k,k′) q-channel tables for the per-spin LR
# exchange (hybrids only). Shares the J^LR w/K_max envelope.
x_lr_cache = None
if exchange_split_active and n_k > 1 and (alpha_hf > 0.0 or _patom_seed_pending):
from .bipole_fock_ewald import build_k_exchange_long_range_cache
assert j_lr_cache is not None and ewald_k_max is not None
x_lr_cache = build_k_exchange_long_range_cache(
basis,
system,
j_lr_cache,
K_max=ewald_k_max,
)
plog.info(
f" K^LR q-channels: {n_k} distinct q = k-k′ shifts on the "
f"shared K_max = {ewald_k_max:.2f} bohr⁻¹ envelope "
f"(per spin, a_HF = {alpha_hf:g})"
)
def _split_k_density_list(density) -> List[np.ndarray]:
return unrestricted_split_k_density_list(
density, n_k=n_k, k_points=k_points, bvk_mesh=_bvk_mesh
)
# Incremental/differential J_SR(+K_SR) accumulators (opt-in; see
# run_pbc_bipole_rhf). Hybrids build per-spin J_SR+K_SR (two
# accumulators on D_a/D_b); pure functionals build J_SR on the total
# density (one accumulator). Corrected gauge + DIIS only.
incremental_jk_alpha = None
incremental_jk_beta = None
incremental_jk_total = None
if use_incremental_fock:
if exchange_split_active and not use_oda:
from .bipole_fock_ewald import IncrementalJK
if alpha_hf > 0.0:
incremental_jk_alpha = IncrementalJK()
incremental_jk_beta = IncrementalJK()
else:
incremental_jk_total = IncrementalJK()
plog.info(
" incremental Fock (differential J_SR/K_SR via ΔD "
"density-envelope screening): ON"
)
else:
plog.info(
" incremental Fock requested but inactive "
"(needs the corrected gauge + DIIS, not ODA)"
)
# (M2d) The UKS two-electron Fock assembly is routed through
# pbc_bipole_fock.build_bipole_unrestricted_fock; the thin wrapper
# below (defined after multipole + SYM3b resolution) adds the
# per-spin V_xc and assembles F(k) in the driver.
# ---- Multipole far-field config (resolve once before SCF loop) -----
from .bipole_fock_multipole import ( # noqa: E402
BipoleMultipoleConfig,
resolve_multipole_config,
)
_mp_config = resolve_multipole_config(
system,
basis,
lat_opts_2e,
user_enable=_ff_enable,
multipole_l_max=multipole_l_max,
)
if _mp_config.enabled:
plog.info(
f" BIPOLE multipole far-field: ENABLED "
f"(L_max={_mp_config.L_max}, R_bipole={_mp_config.R_bipole:.1f} bohr, "
f"n_cells={len(_mp_config.cache.cells) if _mp_config.cache else 0})"
)
else:
plog.info(
f" BIPOLE multipole far-field: off "
f"(R_bipole={_mp_config.R_bipole:.1f} bohr, "
f"cutoff={lat_opts_2e.cutoff_bohr:.1f} bohr)"
)
# SYM3b reduction is automatic for attached-symmetry crystals on the
# corrected split; explicit choices were resolved before the density list.
# ---- Disabled PDR 1988 Ch. II.4c quartet-prototype infrastructure ----
from .bipole_far_field_infrastructure import (
build_bipolar_far_field_infrastructure,
)
_spherical_buffer, _penetration_dispatch_j, _penetration_dispatch_k, _tensor_cache, _fock_kernel, _sym_recon = (
build_bipolar_far_field_infrastructure(
system,
basis,
lat_opts_2e,
use_multipole_far_field=(
(_ff_enable if _ff_enable is not None else False)
and exchange_split_active
),
exchange_split_active=exchange_split_active,
multipole_l_max=multipole_l_max,
ewald_omega=omega_used if use_ewald_j_split else 0.0,
plog=plog,
)
)
# ---- Shared unrestricted Fock-build context (M2d unification) --------
# Bundle the per-run invariants the inline UKS Fock build captured.
# Placed after multipole and symmetry resolution, before the PATOM
# in-field step and SCF loop first call the wrapper.
_fock_ctx = BipoleFockContext(
basis=basis,
system=system,
lat_opts_2e=lat_opts_2e,
use_ewald_j_split=use_ewald_j_split,
exchange_split_active=exchange_split_active,
n_k=n_k,
omega_used=omega_used,
ewald_precision=ewald_precision,
ewald_cell_volume=ewald_cell_volume,
n_elec=n_elec,
xi_madelung=_xi_madelung,
j_lr_cache=j_lr_cache,
x_lr_cache=x_lr_cache,
incremental_jk=None,
rep_cell_indices=_rep_cell_indices,
fock_sym_map=_fock_sym_map,
mp_config=_mp_config,
spherical_moment_buffer=_spherical_buffer,
penetration_dispatch_j=_penetration_dispatch_j,
penetration_dispatch_k=_penetration_dispatch_k,
quartet_tensor_cache=_tensor_cache,
far_field_fock_kernel=_fock_kernel,
symmetry_reconstruction_map=_sym_recon,
s_lat=S_lat,
s_k_list=S_k_list,
k_points=k_points,
weights=weights,
k_points_full=k_points_full,
weights_full=weights_full,
ir_mapping=_ir_mapping,
bvk_mesh=_bvk_mesh,
n_occ=n_alpha,
plog=plog,
sr_image_extent=_sr_image_extent,
exact_zone_bohr=_exact_zone,
)
def _build_fock_for_density(
D_alpha,
D_beta,
*,
coeffs_alpha_for_rho,
coeffs_beta_for_rho,
use_incremental=True,
patom_hf_like=False,
):
fb = build_bipole_unrestricted_fock(
_fock_ctx,
D_alpha,
D_beta,
n_alpha=n_alpha,
n_beta=n_beta,
coeffs_alpha_for_rho=coeffs_alpha_for_rho,
coeffs_beta_for_rho=coeffs_beta_for_rho,
incremental_jk_alpha=incremental_jk_alpha,
incremental_jk_beta=incremental_jk_beta,
incremental_jk_total=incremental_jk_total,
use_incremental=use_incremental,
alpha_hf=alpha_hf,
exchange_assembly=exx,
patom_hf_like=patom_hf_like,
use_reduced_j_only=True,
)
# XC potential -- open-shell UKS API: per-spin V_xc(g) + total
# E_xc. PATOM is an HF-like in-field seed, independent of the
# target functional, so skip XC for that one pre-SCF Fock build.
xc_result = None
if not patom_hf_like:
D_xc_alpha = _density_set_gamma_or_lattice(S_lat, D_alpha)
D_xc_beta = _density_set_gamma_or_lattice(S_lat, D_beta)
xc_result = build_xc_periodic_uks(
basis, system, grid, func, D_xc_alpha, D_xc_beta, lat_opts_2e
)
# Per-k Fock: F_s(k) = F^2e_s(k) + V_xc,s(k) + Hcore(k) −
# K_corr,s(k), hermitised after V_xc so a non-Hermitian Bloch
# sum is symmetrised exactly as the pre-M2d inline build did.
f_alpha_k_list = []
f_beta_k_list = []
F_a_2e_all = _bloch_sum_blocks_multi_k(
fb.f2e_alpha_real.blocks, fb.f2e_alpha_real.cells, k_points
)
F_b_2e_all = _bloch_sum_blocks_multi_k(
fb.f2e_beta_real.blocks, fb.f2e_beta_real.cells, k_points
)
for k_idx, k in enumerate(k_points):
k_arr = np.asarray(k, dtype=float)
F_a_2e = F_a_2e_all[k_idx]
F_b_2e = F_b_2e_all[k_idx]
if xc_result is None:
Vxc_a_k = 0.0
Vxc_b_k = 0.0
else:
Vxc_a_k = np.asarray(bloch_sum(xc_result.V_alpha, k_arr))
Vxc_b_k = np.asarray(bloch_sum(xc_result.V_beta, k_arr))
F_a = F_a_2e + Vxc_a_k + np.asarray(Hcore_k_list[k_idx], dtype=complex)
F_b = F_b_2e + Vxc_b_k + np.asarray(Hcore_k_list[k_idx], dtype=complex)
if fb.k_corr_alpha_per_k is not None:
# Per-spin Ewald exchange split: one matrix per k (a
# single Γ entry at n_k = 1).
F_a = F_a - fb.k_corr_alpha_per_k[k_idx]
F_b = F_b - fb.k_corr_beta_per_k[k_idx]
f_alpha_k_list.append(0.5 * (F_a + F_a.conj().T))
f_beta_k_list.append(0.5 * (F_b + F_b.conj().T))
return _PBCBipoleUKSFockBuild(
f2e_alpha_real=fb.f2e_alpha_real,
f2e_beta_real=fb.f2e_beta_real,
f_alpha_k_list=f_alpha_k_list,
f_beta_k_list=f_beta_k_list,
e_j_short_range=fb.e_j_short_range,
e_j_long_range=fb.e_j_long_range,
e_exchange=fb.e_exchange,
e_j_multipole=fb.e_j_multipole,
e_2e_k_correction=fb.e_2e_k_correction,
e_exchange_finite_size=fb.e_exchange_finite_size,
e_xc=(None if xc_result is None else float(xc_result.e_xc)),
screened_exchange_execution=fb.screened_exchange_execution,
)
if _patom_seed_pending:
plog.info("initial guess: PATOM (SAD + one BIPOLE in-field step)")
patom_fock = _build_fock_for_density(
D_alpha_real,
D_beta_real,
coeffs_alpha_for_rho=None,
coeffs_beta_for_rho=None,
use_incremental=False,
patom_hf_like=True,
)
C_alpha_per_k = []
eps_alpha_per_k = []
C_beta_per_k = []
eps_beta_per_k = []
for idx in range(n_k):
C_a, eps_a = _diag_in_orth_basis(
patom_fock.f_alpha_k_list[idx],
X_k_list[idx],
)
C_b, eps_b = _diag_in_orth_basis(
patom_fock.f_beta_k_list[idx],
X_k_list[idx],
)
C_alpha_per_k.append(C_a)
eps_alpha_per_k.append(eps_a)
C_beta_per_k.append(C_b)
eps_beta_per_k.append(eps_b)
occ_alpha_per_k, mu_alpha, entropy_alpha = _occupations_per_spin(
eps_alpha_per_k, n_alpha
)
occ_beta_per_k, mu_beta, entropy_beta = _occupations_per_spin(
eps_beta_per_k, n_beta
)
entropy = entropy_alpha + entropy_beta
if use_fractional_density:
D_alpha_real = real_space_density_from_kpoints_fractional(
C_alpha_per_k, occ_alpha_per_k, kmesh, cells_density
)
D_beta_real = real_space_density_from_kpoints_fractional(
C_beta_per_k, occ_beta_per_k, kmesh, cells_density
)
if not exchange_split_active:
_zero_cross_cell_density(
D_alpha_real, D_alpha_real.blocks[0].shape[0], n_k
)
_zero_cross_cell_density(
D_beta_real, D_beta_real.blocks[0].shape[0], n_k
)
else:
D_alpha_real = _spin_density(C_alpha_per_k, n_alpha)
D_beta_real = _spin_density(C_beta_per_k, n_beta)
D_alpha_prev = None
D_beta_prev = None
initial_density_is_local = False
density_from_c_per_k = True
plog.banner("SCF (PBC BIPOLE UKS, direct-space)")
plog.info(" iter energy (Ha) dE ||[F,DS]|| DIIS")
# ---- DFT+U setup (Increment 4d-bipole, UKS) -------------------------
dft_plus_u_sites_cxx: List = []
dft_plus_u_ao_groups: List[List[int]] = []
if dft_plus_u:
from ._vibeqc_core import _HubbardSiteCxx
from .dft_plus_u import ao_group_indices
ao_groups_map = ao_group_indices(basis)
for site in dft_plus_u:
key = (site.atom_index, site.l)
if key not in ao_groups_map:
raise ValueError(
f"run_pbc_bipole_uks: HubbardSite{key} has no AOs "
f"in the basis. Available channels: "
f"{sorted(ao_groups_map.keys())}"
)
dft_plus_u_sites_cxx.append(
_HubbardSiteCxx(site.atom_index, site.l, site.U_eff_hartree)
)
dft_plus_u_ao_groups.append(ao_groups_map[key])
def _apply_dft_plus_u(
density_alpha: LatticeMatrixSet,
density_beta: LatticeMatrixSet,
fock_alpha_k: List[np.ndarray],
fock_beta_k: List[np.ndarray],
) -> float:
"""Apply spin-resolved +U to the density used for this Fock."""
if not dft_plus_u_sites_cxx:
return 0.0
from ._vibeqc_core import _compute_dft_plus_u_multi_k_per_spin_cxx
if exchange_split_active:
Pa_k_all = _split_k_density_list(density_alpha)
Pb_k_all = _split_k_density_list(density_beta)
else:
Pa_k_all = _bloch_sum_blocks_multi_k(
density_alpha.blocks, density_alpha.cells, k_points
)
Pb_k_all = _bloch_sum_blocks_multi_k(
density_beta.blocks, density_beta.cells, k_points
)
P_alpha_k_for_u = [
0.5 * (P_k + P_k.conj().T) for P_k in Pa_k_all
]
P_beta_k_for_u = [
0.5 * (P_k + P_k.conj().T) for P_k in Pb_k_all
]
e_alpha, v_alpha = _compute_dft_plus_u_multi_k_per_spin_cxx(
dft_plus_u_sites_cxx,
dft_plus_u_ao_groups,
S_k_list,
P_alpha_k_for_u,
list(weights),
)
e_beta, v_beta = _compute_dft_plus_u_multi_k_per_spin_cxx(
dft_plus_u_sites_cxx,
dft_plus_u_ao_groups,
S_k_list,
P_beta_k_for_u,
list(weights),
)
v_alpha = np.asarray(v_alpha, dtype=complex)
v_beta = np.asarray(v_beta, dtype=complex)
for k_idx, S_k in enumerate(S_k_list):
fock_a = fock_alpha_k[k_idx] + S_k @ v_alpha @ S_k
fock_b = fock_beta_k[k_idx] + S_k @ v_beta @ S_k
fock_alpha_k[k_idx] = 0.5 * (fock_a + fock_a.conj().T)
fock_beta_k[k_idx] = 0.5 * (fock_b + fock_b.conj().T)
return float(e_alpha) + float(e_beta)
scf_trace = []
energy_components = []
E_prev = 0.0
E_elec = 0.0
e_xc = 0.0
e_dft_plus_u = 0.0
F_alpha_k_list = [np.zeros_like(H) for H in Hcore_k_list]
F_beta_k_list = [np.zeros_like(H) for H in Hcore_k_list]
converged = False
iter_idx = 0
#: Exact rebuild from the convergence confirmation (IID 514); reused by
#: the post-loop finalisation so healthy rows pay nothing extra.
_confirm_fb: Optional[_PBCBipoleUKSFockBuild] = None
for iter_idx in range(1, int(opts.max_iter) + 1):
if damper is not None:
damping = damper.alpha
# SPINLOCK PATTERN_HOLD: the accelerator (DIIS / EDIIS / ADIIS /
# KDIIS -- whatever MultiKPeriodicUHFAccelerator resolved) is
# suspended (no history recorded, no extrapolation, damping stays
# live) while the hold is active. Fock extrapolation across
# held-window iterates steers the SCF toward the symmetric attractor
# by continuous orbital rotation -- a collapse the
# occupation-selecting MOM hold cannot see -- and poisons the
# post-release history with out-of-basin iterates. The history
# starts fresh at release.
hold_active = _spinlock_pattern_hold and iter_idx <= _spinlock_iters
diis_active = (
use_diis and iter_idx >= diis_start_iter and not hold_active
)
if iter_idx > 1 and damping > 0.0 and not diis_active:
D_alpha_used = _damp_lattice_matrix(D_alpha_real, D_alpha_prev, damping)
D_beta_used = _damp_lattice_matrix(D_beta_real, D_beta_prev, damping)
else:
D_alpha_used = D_alpha_real
D_beta_used = D_beta_real
d_used_is_damped = iter_idx > 1 and damping > 0.0 and not diis_active
d_used_from_coeffs = (
density_from_c_per_k
and not (initial_density_is_local and iter_idx == 1)
and not d_used_is_damped
)
fock_build = _build_fock_for_density(
D_alpha_used,
D_beta_used,
coeffs_alpha_for_rho=(C_alpha_per_k if d_used_from_coeffs else None),
coeffs_beta_for_rho=(C_beta_per_k if d_used_from_coeffs else None),
)
F_alpha_k_list = fock_build.f_alpha_k_list
F_beta_k_list = fock_build.f_beta_k_list
# ---- DFT+U: per-spin per-k Fock contribution -----------------
# Apply the energy and potential to the same density used by the
# base Fock builder. The converged-density rebuild below uses this
# helper again so the returned energy/Fock/density remain one state.
e_dft_plus_u = _apply_dft_plus_u(
D_alpha_used,
D_beta_used,
F_alpha_k_list,
F_beta_k_list,
)
# XC energy: from the SAME quadrature that produced this
# iteration's per-spin V_xc (inside _build_fock_for_density on
# D_alpha_used/D_beta_used) -- the loop used to run a second,
# redundant build_xc_periodic_uks here every iteration just to
# extract e_xc.
assert fock_build.e_xc is not None
e_xc = float(fock_build.e_xc)
# Energy
D_total_used = _combine_density_sets(
basis, system, lat_opts_2e, D_alpha_used, D_beta_used
)
E_kin = _lattice_contract(D_total_used, T_lat, operator_name="T")
E_ne = _lattice_contract(D_total_used, V_lat, operator_name="V_ne")
E_2e = fock_build.e_2e_k_correction + 0.5 * (
_lattice_contract(
D_alpha_used, fock_build.f2e_alpha_real, operator_name="F2e_alpha"
)
+ _lattice_contract(
D_beta_used, fock_build.f2e_beta_real, operator_name="F2e_beta"
)
)
E_elec = E_kin + E_ne + E_2e + e_xc
# Gradient
grad_norm_sum = 0.0
error_alpha_k_list = []
error_beta_k_list = []
D_alpha_k_list = []
D_beta_k_list = []
D_k_split_guess_a: Optional[List[np.ndarray]] = None
D_k_split_guess_b: Optional[List[np.ndarray]] = None
if exchange_split_active and initial_density_is_local and iter_idx == 1:
# BvK representatives (home block at Γ; exact torus fold at
# multi-k) for local AND wide warm-start storage.
D_k_split_guess_a = _split_k_density_list(D_alpha_used)
D_k_split_guess_b = _split_k_density_list(D_beta_used)
D_k_guess_fold_a: Optional[List[np.ndarray]] = None
D_k_guess_fold_b: Optional[List[np.ndarray]] = None
if (
initial_density_is_local
and iter_idx == 1
and (D_k_split_guess_a is None or D_k_split_guess_b is None)
):
D_k_guess_fold_a = _bloch_sum_blocks_multi_k(
D_alpha_used.blocks, D_alpha_used.cells, k_points
)
D_k_guess_fold_b = _bloch_sum_blocks_multi_k(
D_beta_used.blocks, D_beta_used.cells, k_points
)
for idx in range(n_k):
if initial_density_is_local and iter_idx == 1:
if D_k_split_guess_a is not None and D_k_split_guess_b is not None:
D_a_k = D_k_split_guess_a[idx]
D_b_k = D_k_split_guess_b[idx]
else:
assert D_k_guess_fold_a is not None
assert D_k_guess_fold_b is not None
D_a_k = D_k_guess_fold_a[idx]
D_b_k = D_k_guess_fold_b[idx]
D_a_k = 0.5 * (D_a_k + D_a_k.conj().T)
D_b_k = 0.5 * (D_b_k + D_b_k.conj().T)
else:
C_a = C_alpha_per_k[idx]
C_b = C_beta_per_k[idx]
if not use_fractional_density:
C_a_occ = C_a[:, :n_alpha] if n_alpha > 0 else C_a[:, :0]
C_b_occ = C_b[:, :n_beta] if n_beta > 0 else C_b[:, :0]
D_a_k = C_a_occ @ C_a_occ.conj().T
D_b_k = C_b_occ @ C_b_occ.conj().T
else:
# Fractional-occupation per-spin density
occ_a = np.asarray(occ_alpha_per_k[idx], dtype=float)
occ_b = np.asarray(occ_beta_per_k[idx], dtype=float)
C_a_full = np.asarray(C_a, dtype=np.complex128)
C_b_full = np.asarray(C_b, dtype=np.complex128)
D_a_k = (C_a_full * occ_a[None, :]) @ C_a_full.conj().T
D_b_k = (C_b_full * occ_b[None, :]) @ C_b_full.conj().T
D_alpha_k_list.append(D_a_k)
D_beta_k_list.append(D_b_k)
S_k = S_k_list[idx]
F_a_k = F_alpha_k_list[idx]
F_b_k = F_beta_k_list[idx]
err_a = F_a_k @ D_a_k @ S_k - (F_a_k @ D_a_k @ S_k).conj().T
err_b = F_b_k @ D_b_k @ S_k - (F_b_k @ D_b_k @ S_k).conj().T
error_alpha_k_list.append(err_a)
error_beta_k_list.append(err_b)
grad_norm_sum += float(weights[idx]) * float(
np.sqrt(np.linalg.norm(err_a) ** 2 + np.linalg.norm(err_b) ** 2)
)
E_total = float(E_elec) + e_nuc + e_dft_plus_u
# EXT EL-SPHEROPOLE -- uses total (alpha+beta) density.
D_total_used = _combine_density_sets(
basis, system, lat_opts_2e, D_alpha_used, D_beta_used
)
# EXT EL-SPHEROPOLE -- a 3D-Ewald-gauge correction, identically
# zero in the direct (non-Ewald) gauge used for dim<3.
if system.dim == 3 and not exchange_split_active:
E_sphero = compute_ext_el_spheropole(D_total_used, basis, system, lat_opts)
E_total += E_sphero
else:
E_sphero = None
free_energy = E_total - smearing_T * entropy
dE = free_energy - E_prev if iter_idx > 1 else 0.0
check_scf_divergence(
"run_pbc_bipole_uks", iter_idx, free_energy, grad_norm_sum, dE
)
diis_sub = max(
accel.subspace_size if accel is not None else 0,
accel.subspace_size if accel is not None else 0,
)
scf_trace.append(
SCFIteration(
iter=iter_idx,
energy=float(free_energy),
delta_e=float(dE),
grad_norm=float(grad_norm_sum),
diis_subspace=diis_sub,
)
)
plog.iteration(
iter_idx,
energy=float(free_energy),
dE=float(dE),
grad=float(grad_norm_sum),
diis=diis_sub,
)
energy_components.append(
PBCBipoleEnergyComponents(
iter=int(iter_idx),
e_total=float(E_total),
e_electronic=float(E_elec),
e_kinetic=float(E_kin),
e_nuclear_attraction=float(E_ne),
e_two_electron=float(E_2e),
e_nuclear_repulsion=float(e_nuc),
e_bielet_zone_ee=(None if use_ewald_j_split else float(E_2e)),
e_j_short_range=fock_build.e_j_short_range,
e_j_long_range=fock_build.e_j_long_range,
e_exchange=fock_build.e_exchange,
e_exchange_finite_size=fock_build.e_exchange_finite_size,
e_ext_el_spheropole=E_sphero,
e_dft_plus_u=float(e_dft_plus_u),
)
)
plog.energy_decomposition(
iter_idx,
E_kin=float(E_kin),
E_ne=float(E_ne),
E_2e=float(E_2e),
E_elec=float(E_elec),
E_nuc=float(e_nuc),
)
converged = (
iter_idx > 1
and abs(dE) < float(opts.conv_tol_energy)
and grad_norm_sum < float(opts.conv_tol_grad)
)
# SCF-accelerator extrapolation. Skipped entirely (not even
# recorded) while the PATTERN_HOLD window is active; see the
# hold_active note at the loop head.
if accel is not None and not hold_active:
if exchange_split_active:
# Unprojected Bloch fold: BvK representatives per k
# (home block at Γ; exact torus fold at multi-k).
# Mirrors the RHF accelerator fold; only the bridged
# EDIIS/ADIIS modes consume these densities.
density_alpha_k_list = _split_k_density_list(D_alpha_used)
density_beta_k_list = _split_k_density_list(D_beta_used)
else:
density_alpha_k_list = _bloch_sum_blocks_multi_k(
D_alpha_used.blocks,
D_alpha_used.cells,
k_points,
)
density_beta_k_list = _bloch_sum_blocks_multi_k(
D_beta_used.blocks,
D_beta_used.cells,
k_points,
)
F_a_ex, F_b_ex = accel.extrapolate_uhf(
F_alpha_k_list,
F_beta_k_list,
error_alpha_k_list=error_alpha_k_list,
error_beta_k_list=error_beta_k_list,
density_alpha_k_list=density_alpha_k_list,
density_beta_k_list=density_beta_k_list,
energy=free_energy,
mo_coeffs_alpha_k_list=C_alpha_per_k,
mo_coeffs_beta_k_list=C_beta_per_k,
n_alpha=n_alpha,
n_beta=n_beta,
weights=list(weights),
cells=cells,
kpoints=list(k_points),
)
# On the converged iteration, diagonalise the *physical* Fock
# F(D) -- not the extrapolated one -- so the final orbitals/
# density stay on the converged fixed point. A near-machine-
# zero DIIS error history (SCF nailing the solution in one
# step) makes the Pulay B-matrix singular and its extrapolated
# Fock garbage. See the RHF twin in pbc_bipole.py and
# tests/test_pbc_bipole_diis_converged_basin.py.
if diis_active and not converged:
F_alpha_k_list = F_a_ex
F_beta_k_list = F_b_ex
# --- FMIXING (per-spin, per-k, after DIIS, before level-shift)
# Skipped on the converged iteration (see DIIS note above).
if fock_mixing_value != 0.0 and not converged:
if F_alpha_prev_mixed is not None:
for spin_list, prev_list in [
(F_alpha_k_list, F_alpha_prev_mixed),
(F_beta_k_list, F_beta_prev_mixed),
]:
for idx in range(n_k):
F_mixed = (1.0 - fock_mixing_value) * spin_list[
idx
] + fock_mixing_value * prev_list[idx]
spin_list[idx] = 0.5 * (F_mixed + F_mixed.conj().T)
F_alpha_prev_mixed = [
np.asarray(F, dtype=complex).copy() for F in F_alpha_k_list
]
F_beta_prev_mixed = [
np.asarray(F, dtype=complex).copy() for F in F_beta_k_list
]
# Level shift
if level_shift_schedule is not None:
level_shift_b = level_shift_schedule.at(iter_idx)
else:
level_shift_b = level_shift_static
if level_shift_b != 0.0 and not converged:
F_alpha_for_diag = []
F_beta_for_diag = []
for idx in range(n_k):
S_k = S_k_list[idx]
D_a_k = D_alpha_k_list[idx]
D_b_k = D_beta_k_list[idx]
F_a_shift = apply_level_shift_k(
F_alpha_k_list[idx],
S_k,
D_a_k,
level_shift_b,
LevelShiftDensity.SPIN,
)
F_b_shift = apply_level_shift_k(
F_beta_k_list[idx],
S_k,
D_b_k,
level_shift_b,
LevelShiftDensity.SPIN,
)
F_alpha_for_diag.append(0.5 * (F_a_shift + F_a_shift.conj().T))
F_beta_for_diag.append(0.5 * (F_b_shift + F_b_shift.conj().T))
else:
F_alpha_for_diag = F_alpha_k_list
F_beta_for_diag = F_beta_k_list
# Diagonalise
new_C_alpha = []
new_eps_alpha = []
new_C_beta = []
new_eps_beta = []
for idx in range(n_k):
C_a, eps_a = _diag_in_orth_basis(F_alpha_for_diag[idx], X_k_list[idx])
C_b, eps_b = _diag_in_orth_basis(F_beta_for_diag[idx], X_k_list[idx])
new_C_alpha.append(C_a)
new_eps_alpha.append(eps_a)
new_C_beta.append(C_b)
new_eps_beta.append(eps_b)
# MOM (use_mom: every cycle; SPINLOCK PATTERN_HOLD: cycles
# 2..spinlock_iterations, then release).
_mom_this_iter = use_mom or (
_spinlock_pattern_hold and 1 < iter_idx <= _spinlock_iters
)
if _mom_this_iter and C_prev_occ_alpha_per_k is not None:
for idx in range(n_k):
for spin, (C_k, eps_k, n_occ_spin, C_prev_occ_k) in enumerate(
[
(
new_C_alpha[idx],
new_eps_alpha[idx],
n_alpha,
C_prev_occ_alpha_per_k[idx],
),
(
new_C_beta[idx],
new_eps_beta[idx],
n_beta,
C_prev_occ_beta_per_k[idx],
),
]
):
if n_occ_spin == 0:
continue
S_k = S_k_list[idx]
sel = _mom_select(C_k, S_k, C_prev_occ_k, n_occ_spin, eps_new=eps_k)
n_kept_idx = C_k.shape[1]
virt_mask = np.ones(n_kept_idx, dtype=bool)
virt_mask[sel] = False
virt_sel = np.where(virt_mask)[0]
virt_sel = virt_sel[np.argsort(np.real(eps_k[virt_sel]))]
order = np.concatenate([sel, virt_sel])
if spin == 0:
new_C_alpha[idx] = C_k[:, order]
new_eps_alpha[idx] = eps_k[order]
else:
new_C_beta[idx] = C_k[:, order]
new_eps_beta[idx] = eps_k[order]
C_alpha_per_k = new_C_alpha
eps_alpha_per_k = new_eps_alpha
C_beta_per_k = new_C_beta
eps_beta_per_k = new_eps_beta
occ_alpha_per_k, mu_alpha, entropy_alpha = _occupations_per_spin(
eps_alpha_per_k, n_alpha
)
occ_beta_per_k, mu_beta, entropy_beta = _occupations_per_spin(
eps_beta_per_k, n_beta
)
entropy = entropy_alpha + entropy_beta
if use_fractional_density:
D_alpha_new = real_space_density_from_kpoints_fractional(
C_alpha_per_k, occ_alpha_per_k, kmesh, cells_density
)
D_beta_new = real_space_density_from_kpoints_fractional(
C_beta_per_k, occ_beta_per_k, kmesh, cells_density
)
if not exchange_split_active:
_zero_cross_cell_density(
D_alpha_new, D_alpha_new.blocks[0].shape[0], n_k
)
_zero_cross_cell_density(D_beta_new, D_beta_new.blocks[0].shape[0], n_k)
else:
D_alpha_new = _spin_density(C_alpha_per_k, n_alpha)
D_beta_new = _spin_density(C_beta_per_k, n_beta)
# Require both newly diagonalised spin densities to be the same fixed
# point as D_used before accepting convergence. This includes the
# occupation-only motion that a finite-temperature/Gilat commutator
# cannot see.
if converged:
density_fixed_point_residual = max(
(
float(np.max(np.abs(np.asarray(new) - np.asarray(old))))
for new_set, old_set in (
(D_alpha_new.blocks, D_alpha_used.blocks),
(D_beta_new.blocks, D_beta_used.blocks),
)
for new, old in zip(new_set, old_set)
),
default=0.0,
)
converged = density_fixed_point_residual < float(opts.conv_tol_grad)
# ODA
if use_oda:
fock_naive = _build_fock_for_density(
D_alpha_new,
D_beta_new,
coeffs_alpha_for_rho=C_alpha_per_k,
coeffs_beta_for_rho=C_beta_per_k,
use_incremental=False, # off the per-iter ΔD chain
)
oda_step = _compute_oda_lambda(
D_alpha_used,
D_alpha_new,
F_alpha_k_list,
fock_naive.f_alpha_k_list,
[np.asarray(k) for k in k_points],
weights,
trust_lambda_max=oda_trust_lambda_max,
)
_oda_mix(D_alpha_used, D_alpha_new, oda_step.lam)
_oda_mix(D_beta_used, D_beta_new, oda_step.lam)
D_alpha_prev = D_alpha_real
D_beta_prev = D_beta_real
D_alpha_real = D_alpha_used
D_beta_real = D_beta_used
density_from_c_per_k = oda_step.lam == 1.0
plog.info(
f" ODA: lambda = {oda_step.lam:.4f} (g0 = {oda_step.g0:+.3e}, g1 = {oda_step.g1:+.3e})"
)
else:
D_alpha_prev = D_alpha_used
D_beta_prev = D_beta_used
D_alpha_real = D_alpha_new
D_beta_real = D_beta_new
density_from_c_per_k = True
# Snapshot for next iter MOM (use_mom: every cycle; PATTERN_HOLD: while
# inside the hold window).
if use_mom or (_spinlock_pattern_hold and iter_idx <= _spinlock_iters):
C_prev_occ_alpha_per_k = [
np.asarray(C_alpha_per_k[idx][:, :n_alpha]).copy()
if n_alpha > 0
else np.zeros((C_alpha_per_k[idx].shape[0], 0), dtype=complex)
for idx in range(n_k)
]
C_prev_occ_beta_per_k = [
np.asarray(C_beta_per_k[idx][:, :n_beta]).copy()
if n_beta > 0
else np.zeros((C_beta_per_k[idx].shape[0], 0), dtype=complex)
for idx in range(n_k)
]
if damper is not None:
damper.update(free_energy)
E_prev = free_energy
if converged:
# IID 514: confirm the provisional exit on the EXACT operator at
# the density just committed (see run_pbc_bipole_rhf).
_confirm_fb = _build_fock_for_density(
D_alpha_real,
D_beta_real,
coeffs_alpha_for_rho=(
C_alpha_per_k if density_from_c_per_k else None
),
coeffs_beta_for_rho=(
C_beta_per_k if density_from_c_per_k else None
),
use_incremental=False,
)
_confirm_grad = unrestricted_bipole_commutator_norm(
_confirm_fb.f_alpha_k_list,
_confirm_fb.f_beta_k_list,
(
_split_k_density_list(D_alpha_real)
if exchange_split_active
else _bloch_sum_blocks_multi_k(
D_alpha_real.blocks, D_alpha_real.cells, k_points
)
),
(
_split_k_density_list(D_beta_real)
if exchange_split_active
else _bloch_sum_blocks_multi_k(
D_beta_real.blocks, D_beta_real.cells, k_points
)
),
S_k_list,
weights,
)
converged = (
_confirm_grad < float(opts.conv_tol_grad)
and abs(dE) < float(opts.conv_tol_energy)
)
if not converged:
_confirm_fb = None
if converged:
break
# BZ-weighted complex <S^2>; valid for Gamma-containing and shifted
# meshes and for fractional fixed-spin occupations.
from .periodic_k_gdf import _multi_k_s_squared
s2 = _multi_k_s_squared(
n_alpha,
n_beta,
C_alpha_per_k,
C_beta_per_k,
S_k_list,
weights,
occ_alpha_k=occ_alpha_per_k,
occ_beta_k=occ_beta_per_k,
)
# ---- Ionic-Γ basin-health diagnostic (smearing straddle, per spin) -
# See run_pbc_bipole_rks / smearing_basin_warning. Both spin channels
# are checked; the minimum per-k gap across spins governs the trigger.
basin_warning = smearing_basin_warning(
smearing_T,
[
(eps_alpha_per_k, occ_alpha_per_k, n_alpha, 1.0),
(eps_beta_per_k, occ_beta_per_k, n_beta, 1.0),
],
entropy,
"run_pbc_bipole_uks",
)
if basin_warning is not None:
plog.info(" WARNING: " + basin_warning)
warnings.warn(basin_warning, UserWarning, stacklevel=2)
screened_exchange_execution = fock_build.screened_exchange_execution
final_e_xc = float(e_xc)
final_e_2e = float(E_2e)
final_e_exchange = float(fock_build.e_exchange or 0.0)
# ---- Post-loop: evaluate the exact density returned to callers. The
# last diagonalisation commits a new density even when the iteration
# budget is exhausted; always rebuild to keep the result internally
# consistent.
with bipole_final_density_phase(
plog,
iter_idx=iter_idx,
energy=E_total,
converged=converged,
n_k=n_k,
nbf=basis.nbasis,
):
_fb = (
_confirm_fb
if _confirm_fb is not None
else _build_fock_for_density(
D_alpha_real,
D_beta_real,
coeffs_alpha_for_rho=(
C_alpha_per_k if density_from_c_per_k else None
),
coeffs_beta_for_rho=(
C_beta_per_k if density_from_c_per_k else None
),
use_incremental=False,
)
)
F_alpha_k_list = _fb.f_alpha_k_list
F_beta_k_list = _fb.f_beta_k_list
e_dft_plus_u = _apply_dft_plus_u(
D_alpha_real,
D_beta_real,
F_alpha_k_list,
F_beta_k_list,
)
screened_exchange_execution = _fb.screened_exchange_execution
D_xc_a = _density_set_gamma_or_lattice(S_lat, D_alpha_real)
D_xc_b = _density_set_gamma_or_lattice(S_lat, D_beta_real)
_xc = build_xc_periodic_uks(
basis, system, grid, func, D_xc_a, D_xc_b, lat_opts_2e
)
D_tot = _combine_density_sets(
basis, system, lat_opts_2e, D_alpha_real, D_beta_real
)
E_kin_f = _lattice_contract(D_tot, T_lat, operator_name="T")
E_ne_f = _lattice_contract(D_tot, V_lat, operator_name="V_ne")
E_2e_f = _fb.e_2e_k_correction + 0.5 * (
_lattice_contract(D_alpha_real, _fb.f2e_alpha_real, operator_name="F2e")
+ _lattice_contract(D_beta_real, _fb.f2e_beta_real, operator_name="F2e")
)
E_elec = E_kin_f + E_ne_f + E_2e_f + float(_xc.e_xc)
final_e_xc = float(_xc.e_xc)
final_e_2e = float(E_2e_f)
final_e_exchange = float(_fb.e_exchange or 0.0)
E_total = float(E_elec) + e_nuc + e_dft_plus_u
# Fresh E_total doesn't include spheropole -- add it (3D only; the
# term is zero in the direct gauge used for dim<3).
if system.dim == 3 and not exchange_split_active:
E_sphero_final = compute_ext_el_spheropole(D_tot, basis, system, lat_opts)
E_total += E_sphero_final
else:
E_sphero_final = None
energy_components[-1] = PBCBipoleEnergyComponents(
iter=int(iter_idx),
e_total=float(E_total),
e_electronic=float(E_elec),
e_kinetic=float(E_kin_f),
e_nuclear_attraction=float(E_ne_f),
e_two_electron=float(E_2e_f),
e_nuclear_repulsion=float(e_nuc),
e_bielet_zone_ee=(
None if use_ewald_j_split else float(E_2e_f)
),
e_ext_el_spheropole=E_sphero_final,
e_j_short_range=_fb.e_j_short_range,
e_j_long_range=_fb.e_j_long_range,
e_exchange=_fb.e_exchange,
e_exchange_finite_size=_fb.e_exchange_finite_size,
e_j_multipole=_fb.e_j_multipole,
e_dft_plus_u=float(e_dft_plus_u),
)
# The converged-density rebuild above can change E_total. Keep the
# reported thermodynamic objective on that same final density; computing
# it before the rebuild returned a stale Mermin free energy for UKS.
free_energy_final = E_total - smearing_T * entropy
final_grad_norm = unrestricted_bipole_commutator_norm(
F_alpha_k_list,
F_beta_k_list,
(
_split_k_density_list(D_alpha_real)
if exchange_split_active
else _bloch_sum_blocks_multi_k(
D_alpha_real.blocks, D_alpha_real.cells, k_points
)
),
(
_split_k_density_list(D_beta_real)
if exchange_split_active
else _bloch_sum_blocks_multi_k(
D_beta_real.blocks, D_beta_real.cells, k_points
)
),
S_k_list,
weights,
)
final_delta, _ = refresh_bipole_terminal_trace(
scf_trace,
float(free_energy_final),
grad_norm=final_grad_norm,
)
if converged:
converged = (
abs(final_delta) < float(opts.conv_tol_energy)
and final_grad_norm < float(opts.conv_tol_grad)
)
plog.converged(
n_iter=iter_idx,
energy=free_energy_final,
converged=converged,
)
return PBCBipoleUKSResult(
energy=float(E_total),
e_electronic=float(E_elec),
e_nuclear=e_nuc,
e_ext_el_spheropole=E_sphero_final,
e_xc=final_e_xc,
e_coulomb=final_e_2e - final_e_exchange,
e_hf_exchange=final_e_exchange,
n_iter=iter_idx,
converged=converged,
s_squared=float(s2),
s_squared_ideal=0.25 * (mult - 1) * (mult + 1),
mo_energies_alpha=eps_alpha_per_k,
mo_coeffs_alpha=C_alpha_per_k,
fock_alpha=F_alpha_k_list,
density_alpha=D_alpha_real,
mo_energies_beta=eps_beta_per_k,
mo_coeffs_beta=C_beta_per_k,
fock_beta=F_beta_k_list,
density_beta=D_beta_real,
overlap=S_k_list,
hcore=Hcore_k_list,
scf_trace=scf_trace,
ewald_alpha_bohr_inv=omega_used,
sr_image_extent_bohr=_sr_image_extent,
pair_resolved_fock_domain=bool(_fock_sym_map is not None),
e_dft_plus_u=float(e_dft_plus_u),
energy_components=energy_components,
exchange_ewald_split=bool(exchange_split_active),
exchange_exxdiv=(exchange_exxdiv if exchange_split_active else None),
overlap_fold_drift=overlap_fold_drift,
exact_zone_bohr=_exact_zone,
screened_exchange_execution=screened_exchange_execution,
basin_warning=basin_warning,
functional=str(opts.functional),
smearing_temperature=smearing_T,
fermi_level=float(mu_alpha) if n_alpha > 0 else float(mu_beta),
fermi_level_alpha=(float(mu_alpha) if n_alpha > 0 else None),
fermi_level_beta=(float(mu_beta) if n_beta > 0 else None),
entropy=float(entropy),
free_energy=float(free_energy_final),
occupations_alpha=[np.asarray(o, dtype=float) for o in occ_alpha_per_k],
occupations_beta=[np.asarray(o, dtype=float) for o in occ_beta_per_k],
kpoints_cart=np.asarray(k_points, dtype=float).reshape(-1, 3),
kpoint_weights=np.asarray(weights, dtype=float).reshape(-1),
fock_mixing=fock_mixing_value,
)