Source code for vibeqc.pbc_bipole_rks

"""BIPOLE-style periodic RKS driver in CRYSTAL's electrostatic gauge.

The DFT counterpart of :mod:`vibeqc.pbc_bipole`. Pure functionals use
the exact analytical-FT, G=0-dropped periodic Hartree J in the same
neutral-background convention as the GDF reference; hybrid functionals
retain the CRYSTAL-gauge Ewald split so the HF exchange correction can
share the native ``build_jk_2e_real_space`` component builder.

This driver keeps the same multi-k SCF scaffold as the RHF 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 (
    BasisSet,
    BlochKMesh,
    EwaldOptions,
    Functional,
    GridOptions,
    InitialGuess,
    LatticeMatrixSet,
    LatticeSumOptions,
    PeriodicKSOptions,
    PeriodicSystem,
    SCFIteration,
    bloch_sum,
    build_grid,
    build_xc_periodic,
    direct_lattice_cells,
    ewald_nuclear_repulsion,
    nuclear_repulsion_per_cell,
    real_space_density_from_kpoints,
    real_space_density_from_kpoints_fractional,
)
from .bipole_ext_el_pole import compute_ext_el_spheropole
from .guess import 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,
    PBCBipoleEnergyComponents,
    _bloch_sum_blocks,
    _bloch_sum_blocks_multi_k,
    _compute_nuclear_lattice_ewald_reciprocal_ft,
    _crystal_ewald_options,
    _density_set_gamma_or_lattice,
    _emit_bipole_semantic_diagnostic,
    _expand_ibz_kmesh_for_ewald_j,
    _lattice_contract,
    _zero_cross_cell_density,
    bloch_h_core_and_orthogonalizer,
    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,
    restricted_bipole_commutator_norm,
    refresh_bipole_terminal_trace,
    resolve_fock_mixing,
    resolve_auto_fock_mixing,
    resolve_bipole_sr_image_extent,
    resolve_bipole_fock_symmetry,
    resolve_incremental_jk,
    warn_bipole_exact_j_core_tail,
    warn_bipole_charged_cell,
    warn_bipole_legacy_multik_gauge,
    smearing_basin_warning,
)
from .pbc_bipole_fock import (
    BipoleFockContext,
    BipoleOutputCellFarmingExecution,
    BipoleScreenedExchangeExecution,
    build_bipole_restricted_fock,
    split_k_density_list,
)
from .periodic_grid import build_periodic_becke_grid
from .periodic_rhf_multi_k_ewald import (
    _damp_lattice_matrix,
    _diag_in_orth_basis,
)
from .periodic_scf_accelerators import (
    DynamicDamping,
    MultiKPeriodicSCFAccelerator,
)
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,
    occupations_are_per_k_integer_aufbau as _occupations_are_per_k_integer_aufbau,
)
from .symmetry_integrals_reduced import (
    compute_nuclear_lattice_reduced,
)

__all__ = [
    "PBCBipoleRKSResult",
    "run_pbc_bipole_rks",
]


[docs] @dataclass class PBCBipoleRKSResult: """Result of :func:`run_pbc_bipole_rks`.""" energy: float e_electronic: float e_nuclear: float e_xc: float e_coulomb: float e_hf_exchange: float n_iter: int converged: bool mo_energies: List[np.ndarray] mo_coeffs: List[np.ndarray] fock: List[np.ndarray] overlap: List[np.ndarray] hcore: List[np.ndarray] density: LatticeMatrixSet 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(...)]``. e_dft_plus_u: float = 0.0 energy_components: List[PBCBipoleEnergyComponents] = field( default_factory=list, ) 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: List[np.ndarray] = field(default_factory=list) # Gauge provenance (option (b)): True when the run used the # corrected gauge (full-Bloch density, no spheropole, a_HF-scaled # Ewald exchange split for hybrids). 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); carries # the warning message. See smearing_basin_warning. basin_warning: Optional[str] = None # Cartesian k-points (bohr^-1) and weights this result spans, in the # same order as the per-k ``mo_coeffs`` / ``mo_energies`` lists. Lets # optional Gamma-only / 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 1: radius (bohr) of the exact erfc # output zone when restricted below the operator cutoff (None = # exact zone == cutoff). Analytic-gradient consumers fail closed # on a set value (FD remains the production force path). exact_zone_bohr: Optional[float] = None output_cell_farming_execution: Optional[ BipoleOutputCellFarmingExecution ] = None
@dataclass class _PBCBipoleRKSFockBuild: """Internal Fock-build bundle for the BIPOLE RKS driver.""" f2e_real: LatticeMatrixSet f_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 exchange correction (Ewald exchange split, a_HF-scaled): # lives in F(k), so its energy must be added to the # lattice-contracted E_2e by the caller. 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 V_xc entered f_k_list. # Consuming this instead of re-running build_xc_periodic keeps the # iteration's V_xc and e_xc from one build (they used to come from # two independent quadratures per iteration -- one discarded). e_xc: Optional[float] = None screened_exchange_execution: Optional[ BipoleScreenedExchangeExecution ] = None output_cell_farming_execution: Optional[ BipoleOutputCellFarmingExecution ] = None
[docs] def run_pbc_bipole_rks( 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, multipole_l_max: int = 2, use_exact_ft_j: bool = False, use_exchange_ewald_split: Optional[bool] = None, exchange_exxdiv: str = "ewald", 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, farm_output_cells: bool = False, output_cell_farming_strategy: str = "cyclic", output_cell_farming_task_kind: str = "direct-eri-output-cell", progress: Union[bool, ProgressLogger, None] = None, verbose: Optional[int] = None, initial_density: Optional[Sequence[np.ndarray]] = None, dft_plus_u: Optional[List["HubbardSite"]] = None, bz_integration: Optional[str] = None, ) -> PBCBipoleRKSResult: """Multi-k closed-shell RKS via the CRYSTAL-gauge BIPOLE scaffold. Parameters ---------- system, basis, kmesh As in :func:`run_pbc_bipole_rhf`. options :class:`PeriodicKSOptions` or None for PBE defaults. functional XC functional name (overrides ``options.functional`` if given). fock_mixing Optional previous-Fock weight override in ``[0, 1)``. The caller's ``options.fock_mixing`` field is not rewritten. A resolved zero can still activate the documented DIIS-off KS automatic value. use_exchange_ewald_split, exchange_exxdiv Exchange/gauge convention (option (b), 2026-06-11). ``None`` = auto: the corrected gauge is ON at 3D Γ-only sampling under the Ewald J split -- full-Bloch density (no Γ-locality projection, which also fixes the XC grid density r(r): the projected density dropped the cross-cell AO products), no EXT EL-SPHEROPOLE term, and for hybrids (a_HF > 0) the Ewald exchange split ``K = K_SR(erfc w) + K_LR(reciprocal K!=0) + (ξ_M - pi/(Vw^2)).S.D.S`` scaled by a_HF. Pure functionals need no exchange machinery -- the gauge change alone applies (and the wasted full-Coulomb K traversal of the legacy path is skipped). See :func:`run_pbc_bipole_rhf` for the full convention notes. The corrected gauge is the default at BOTH Γ and multi-k (Phase-5 flip 2026-06-13): at multi-k it adds the q = k-k′ LR-exchange channels + BvK-supercell Madelung correction (requires a Monkhorst-Pack mesh; an ad-hoc k-list falls back to the legacy gauge under the auto default). Pass ``use_exchange_ewald_split=False`` for the legacy gauge. bz_integration ``None`` / ``"smearing"`` use the existing Aufbau or Fermi-Dirac occupation path. ``"gilat"`` selects the parameter-free Gilat-Raubenheimer net at T = 0; it cannot be combined with finite-temperature smearing. sr_image_precision, sr_image_extent_bohr M5 erfc SR image-domain controls; see :func:`run_pbc_bipole_rhf`. Pure semilocal RKS routes its Hartree J through the same padded SR+LR erfc composition as every other route (exact-FT retirement, 2026-07-18), so these controls apply to it. Screened hybrids pad the shared SR J base; their dedicated screened exchange traversal is a separate implementation path. use_exact_ft_j Opt-in cross-check oracle (default ``False``): route the pure semilocal Hartree J through the exact analytic-FT Ewald builder (``VIBEQC_J_EWALD3D_KE`` reciprocal cutoff, default 200 Ha) instead of the production padded SR+LR composition. The oracle's finite-ke reciprocal tail undercounts *absolute* totals on dense-core cells (~0.5-1 Ha at ke=200 on MgO-class bases; the run warns with the required ke estimate) while cancelling in energy differences. Pure functionals on the corrected split only; fails closed otherwise. use_fock_symmetry_reduce ``None`` auto-enables pair-resolved reduction for attached-symmetry crystals on the corrected split. See :func:`run_pbc_bipole_rhf` for the explicit opt-out and enforcement-only forms. farm_output_cells Distribute complete direct-ERI real-space output blocks across MPI ranks and gather them before incremental Fock bookkeeping. Every task retains the full internal translation sum. Generic BIPOLE callers leave this off; the chi-CCM restricted four-center selector supplies ``"chi-direct-output-cell"`` as its execution label. Screened hybrids fail closed because their separate J and screened-K phases require a multi-phase execution record. All other parameters As in :func:`run_pbc_bipole_rhf`. Returns ------- PBCBipoleRKSResult """ reject_bipole_quartet_far_field( use_multipole_far_field, driver="run_pbc_bipole_rks", ) reject_bipole_lone_non_gamma_kpoint( kmesh, driver="run_pbc_bipole_rks", ) 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_rks", basis=basis, system=system, ) reject_bipole_solver_options(opts, driver="run_pbc_bipole_rks") if int(opts.max_iter) < 1: raise ValueError("run_pbc_bipole_rks: max_iter must be at least 1") if not isinstance(farm_output_cells, (bool, np.bool_)): raise TypeError("run_pbc_bipole_rks: farm_output_cells must be bool") farm_output_cells = bool(farm_output_cells) if output_cell_farming_strategy not in ("block", "cyclic"): raise ValueError( "run_pbc_bipole_rks: output_cell_farming_strategy must be " "'block' or 'cyclic'" ) if ( not isinstance(output_cell_farming_task_kind, str) or not output_cell_farming_task_kind.strip() ): raise ValueError( "run_pbc_bipole_rks: output_cell_farming_task_kind must be a " "non-empty string" ) if use_oda: raise NotImplementedError( "run_pbc_bipole_rks: ODA is unavailable because a mixed " "line-search density has no single orbital representation; " "use DIIS instead" ) 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_rks: smearing_temperature must be >= 0") if bz_integration is not None: bz_integration = str(bz_integration).strip().lower() if bz_integration not in ("smearing", "gilat"): raise ValueError( "run_pbc_bipole_rks: bz_integration must be None, " f"'smearing', or 'gilat'; got {bz_integration!r}" ) use_gilat = bz_integration == "gilat" if use_gilat and smearing_T > 0.0: raise NotImplementedError( "run_pbc_bipole_rks: bz_integration='gilat' is a " "sharp-Fermi-surface occupation backend and cannot be combined " "with finite-temperature smearing." ) use_fractional_occupations = smearing_T > 0.0 or use_gilat func = Functional(opts.functional, 1) # spin-unpolarised reject_bipole_unsupported_ks_functional( func, driver="run_pbc_bipole_rks", ) # CAM exchange assembly. alpha_hf is the FULL-RANGE exact-exchange # fraction and drives the Ewald exchange-split machinery (xi_M, # K_LR q-channels, K_corr). Screened hybrids (hse06) have c_full # = 0 -- none of that machinery engages; their erfc short-range K # is added inside build_bipole_restricted_fock (no seam, no # far-field, per the CRYSTAL RSH treatment). LR-heavy RSH fails # closed in the resolver. exx = resolve_periodic_exchange(func, where="run_pbc_bipole_rks") alpha_hf = float(exx.c_full) if farm_output_cells and exx.is_screened: raise NotImplementedError( "run_pbc_bipole_rks: direct-ERI output-cell farming is not " "available for screened hybrids because the current single-phase " "execution record cannot attest both the base J and separate " "screened-K traversals" ) # CRYSTAL-style auto-FMIXING: fires only for DFT without DIIS (see # resolve_auto_fock_mixing for the Gap-B measurement basis). requested_fock_mixing = resolve_fock_mixing( opts, fock_mixing, where="run_pbc_bipole_rks", ) fock_mixing_value = resolve_auto_fock_mixing( requested_fock_mixing, alpha_hf=alpha_hf, use_diis=bool(opts.use_diis), where="run_pbc_bipole_rks", ) 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) plog.info( f"PBC BIPOLE RKS (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}" ) if use_gilat: plog.info(" bz integration = Gilat-Raubenheimer sharp-Fermi net") plog.info( f" F^2e (J + V_xc{'+ K' if exx.needs_exchange else ''}) : " f"{'EWALD_J_SPLIT' if use_ewald_j_split else lat_opts_2e.coulomb_method.name}" ) n_elec = system.n_electrons() if n_elec % 2 != 0: raise ValueError( f"run_pbc_bipole_rks: closed-shell RKS requires even electron " f"count; got {n_elec}" ) if system.multiplicity != 1: raise ValueError( f"run_pbc_bipole_rks: requires multiplicity=1; got {system.multiplicity}" ) n_occ = n_elec // 2 _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 initial_density is None and getattr(opts, "initial_guess", InitialGuess.HCORE) == InitialGuess.READ ): raise NotImplementedError( "run_pbc_bipole_rks: multi-k READ requires an explicit complete " "real-space initial_density block set; a Gamma-only read_density " "cannot reconstruct the per-k Bloch density." ) plog.info( f"k-mesh: {n_k} k-point{'s' if n_k != 1 else ''}, " f"weights sum = {weights.sum():.4f}" ) # ---- Exchange/gauge resolution (option (b), 2026-06-11) ---------- # Mirrors run_pbc_bipole_rhf: corrected gauge at 3D Γ under the J # split (full-Bloch density, no spheropole; a_HF-scaled Ewald # exchange split for hybrids). Multi-k: explicit opt-in runs the # q!=0 LR-exchange channels (Phase 3); auto stays legacy pending # certification. if exchange_exxdiv not in ("ewald", "none"): raise ValueError( f"run_pbc_bipole_rks: 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_rks: use_exchange_ewald_split=True requires " "the Ewald J split (use_ewald_j_split=True)." ) # Multi-k split (option (b) Phase 3): q-channel tables, the # BvK-torus density fold, and the supercell Madelung correction # all need the true Monkhorst-Pack dimensions; ad-hoc k-lists # (mesh = (1,1,1) placeholders) 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_rks: 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_occupations, driver="run_pbc_bipole_rks", ) 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"; exchange split exxdiv={exchange_exxdiv}, " f"a_HF={alpha_hf:g}" + ( f", ξ_M = {_xi_madelung:.6f} Ha" if exchange_exxdiv == "ewald" else "" ) if alpha_hf > 0.0 else "; pure functional -- no HF exchange" ) + ")" ) # Exact-FT retirement (maintainer ruling 2026-07-13, landed # 2026-07-18): pure semilocal RKS defaults to the same padded SR+LR # Ewald-J composition as every other erfc route. The M4b # interaction-resolved screening plus the M5 ``sr_image_precision`` # padding repaired the historical SR ket-image truncation that # motivated the exact-FT default, while the exact-FT builder's # finite-ke reciprocal core tail undercounts absolute totals on # dense-core cells by ~0.5-1 Ha at the default ke=200 (cancels in # differences; breaks absolute CRYSTAL/PySCF parity). The analytic-FT # builder stays available as the explicit ``use_exact_ft_j`` # cross-check oracle and fails closed off its validated envelope. if use_exact_ft_j: if alpha_hf != 0.0 or exx.needs_exchange: raise ValueError( "run_pbc_bipole_rks: use_exact_ft_j is the pure-functional " "exact-FT J cross-check oracle; it does not apply to hybrid " f"or screened-hybrid functionals (a_HF = {alpha_hf:g}, " f"screened = {bool(exx.is_screened)})." ) if not (use_ewald_j_split and exchange_split_active): raise ValueError( "run_pbc_bipole_rks: use_exact_ft_j requires the corrected " "exchange-split gauge under the Ewald J split (3D periodic " "Monkhorst-Pack sampling); the legacy gauge has no exact-FT " "J route." ) if use_multipole_far_field: raise ValueError( "run_pbc_bipole_rks: use_exact_ft_j cannot be combined " "with the retired multipole far-field research artifact." ) use_exact_ewald_j_for_pure_rks = bool(use_exact_ft_j) exact_j_ke_cutoff = 200.0 exact_j_chunk_size = 512 if use_exact_ewald_j_for_pure_rks: import os exact_j_ke_cutoff = float(os.environ.get("VIBEQC_J_EWALD3D_KE", "200.0")) exact_j_chunk_size = max( 1, int(os.environ.get("VIBEQC_J_EWALD3D_CHUNK", "512")), ) plog.info( " Pure-RKS Hartree J: exact analytic-FT Ewald cross-check " f"oracle (G=0 dropped, ke_cutoff={exact_j_ke_cutoff:g} Ha)" ) warn_bipole_exact_j_core_tail(basis, exact_j_ke_cutoff, plog) # ---- Shared Ewald state (one a across V_ne / E_nn / J_LR) ------- ewald_options_1e: Optional[EwaldOptions] = None omega_used: Optional[float] = None ewald_cell_volume: Optional[float] = 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, ) _erfc_sr_build_active = ( not use_exact_ewald_j_for_pure_rks or bool(exx.is_screened) ) # The shared padded ket-image ball must converge both active erfc # kernels. HSE06's screened exchange (omega=0.11) can be longer-ranged # than the Ewald J kernel, 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, # The opt-in exact-FT J oracle has no erfc SR traversal to pad; # every production route (incl. pure RKS since the exact-FT # retirement) and screened hybrids pad the shared J/K domain. erfc_sr_build_active=_erfc_sr_build_active, plog=plog, ) if farm_output_cells and ( not exchange_split_active or _sr_image_extent is None ): raise NotImplementedError( "run_pbc_bipole_rks: direct-ERI output-cell farming currently " "requires the corrected 3D Ewald exchange split and a padded " "short-range image domain" ) # ---- DFT grid ---------------------------------------------------- # Wrapped in plog.stage so a job that stalls here (periodic Becke # partitioning over image cells can be minutes on dense/large cells) # shows ``[dft_grid]`` as its last live line instead of going dark -- # the pre-SCF setup that walltimed P13 MgO BIPOLE/XC left no marker # localizing which stage was slow. with plog.stage( "dft_grid", detail=( "periodic Becke" if getattr(opts, "use_periodic_becke", False) else "molecular grid on unit cell" ), ): 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) # ---- Real-space 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="plain", ) cells = list(S_lat.cells) plog.info(f"n_cells in lattice sum = {len(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, exchange_split_active=exchange_split_active, auto_reduce_safe=( not _erfc_sr_build_active or _sr_image_extent is not None ), ) _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="rks", 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 tensor has " f"{_fock_sym_map.density_domain.n_triples} qualifying pairs)" ) 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 " f"(2x cutoff -- resolves every P(b-a) difference)" ) else: cells_density = cells # ---- Per-k S(k), Hcore(k), X(k) --------------------------------- from .linear_dependence import ( check_overlap_matrix, format_linear_dependence_report, raise_if_severe, scf_preflight_overlap_check, ) S_k_list: List[np.ndarray] = [] Hcore_k_list: List[np.ndarray] = [] X_k_list: List[np.ndarray] = [] overlap_reports = [] for k_idx, k in enumerate(k_points): k_arr = np.asarray(k, dtype=float).reshape(3) S_k, T_k, V_k, H_k, X_k, n_kept = bloch_h_core_and_orthogonalizer( S_lat, T_lat, V_lat, k_arr, linear_dep_threshold, canonical_orth_normalize_diag_first, ) overlap_label = f"S(k={k_idx}, k_cart={k_arr.round(4).tolist()})" if n_k <= 16: report = scf_preflight_overlap_check( S_k, plog=plog, label=overlap_label, basis=basis, ) else: report = check_overlap_matrix( S_k, basis=basis, label=overlap_label, ) if report.severity != "ok": prefix = { "warn": "WARN", "error": "ERROR", "critical": "CRITICAL", }[report.severity] plog.info( f"[{prefix}] overlap [{overlap_label}]: " f"nbf={report.n_basis}, " f"min eig={report.min_eigenvalue:+.2e}, " f"cond={report.condition_number:.2e}" ) plog.write_raw(format_linear_dependence_report(report)) raise_if_severe(report) overlap_reports.append(report) if n_occ > n_kept: raise RuntimeError( f"run_pbc_bipole_rks: canonical orth at k={k_idx} " f"dropped too many directions (n_occ={n_occ}, " f"n_kept={n_kept})" ) S_k_list.append(S_k) Hcore_k_list.append(H_k) X_k_list.append(X_k) # ---- Nuclear repulsion ------------------------------------------- if ewald_options_1e is not None: e_nuc = float(ewald_nuclear_repulsion(system, ewald_options_1e)) else: e_nuc = float(nuclear_repulsion_per_cell(system, lat_opts_1e)) plog.info(f"E_nuc per cell = {e_nuc:+.10f} Ha") # ---- Initial guess ----------------------------------------------- C_per_k: List[np.ndarray] = [] eps_per_k: List[np.ndarray] = [] for H_k, X_k in zip(Hcore_k_list, X_k_list): C_k, eps_k = _diag_in_orth_basis(H_k, X_k) C_per_k.append(C_k.astype(complex)) eps_per_k.append(eps_k) n_occ_per_k = [n_occ] * n_k n_electrons_per_cell = float(n_elec) def _occupations_from_eps( eps_per_k_local: Sequence[np.ndarray], ) -> Tuple[List[np.ndarray], float, float]: if use_gilat: from .bz_integration import gilat_occupations_for_kmesh occ_gr, ef_gr = gilat_occupations_for_kmesh( system, kmesh, eps_per_k_local, n_electrons_per_cell, spin_degeneracy=2.0, ) return occ_gr, float(ef_gr), 0.0 return _closed_shell_periodic_occupations( eps_per_k_local, weights, n_electrons_per_cell, n_occ, smearing_T, ) occ_per_k, fermi_level, entropy = _occupations_from_eps(eps_per_k) def _fractional_density_needed( occ_per_k_local: Sequence[np.ndarray], ) -> bool: """Whether these occupations need the occupation-driven builder. The fixed ``C[:, :n_occ]`` slice builder is exact only for the legacy per-k integer Aufbau pattern. The T = 0 fill is one global Fermi level over the mesh (#85), so a band-overlap mesh can occupy a different number of bands per k (or a shared fractional group at mu), which no fixed slice reproduces; those occupations must be built from themselves, as the native multi-k GDF route does (#509). """ if _occupations_are_per_k_integer_aufbau(occ_per_k_local, n_occ): return False reject_bipole_fractional_legacy_gauge( use_ewald_j_split=bool(use_ewald_j_split), exchange_split_active=exchange_split_active, fractional_occupations=True, # runtime-discovered band-overlap fill driver="run_pbc_bipole_rks", ) if use_mom or use_oda: raise NotImplementedError( "run_pbc_bipole_rks: the zero-temperature Brillouin-zone fill " "is not per-k-integer-aufbau on this mesh (the bands overlap " "the Fermi level), so there is no sharp occupied subspace for " "use_mom/use_oda. Disable use_mom/use_oda or add finite " "smearing." ) return True # Per-k -> real-space density fold over the wide (2x-cutoff) cell list # is O(n_k x Ncells x Nbf^2) and silent; a prime multi-k cost for the # LDA (2,2,2) row, so bracket it for localization. with plog.stage( "initial_density_fold", detail=f"per-k SAD/Hcore -> real space over {len(cells_density)} cells", ): if _fractional_density_needed(occ_per_k): D_real = real_space_density_from_kpoints_fractional( C_per_k, occ_per_k, kmesh, cells_density, ) else: D_real = real_space_density_from_kpoints( C_per_k, n_occ_per_k, kmesh, cells_density, ) if not exchange_split_active: _zero_cross_cell_density(D_real, basis.nbasis, n_k) # Caller-supplied warm-start density takes precedence over the # SAD/Hcore guess engine. Block ordering matches the canonical # ``direct_lattice_cells(kmesh)`` ordering -- same contract as the # RHF driver. Used by the NEB driver for within-image density # warm-start for periodic NEB. if initial_density is not None: blocks_in = list(initial_density) if len(blocks_in) != len(D_real.cells): raise ValueError( f"run_pbc_bipole_rks: initial_density has " f"{len(blocks_in)} blocks; expected {len(D_real.cells)}" ) for g_idx, block in enumerate(blocks_in): D_real.set_block(g_idx, np.asarray(block, dtype=float)) plog.info("initial guess: caller-supplied density (warm-start)") initial_density_is_local = True density_from_c_per_k = False else: guess = getattr(opts, "initial_guess", InitialGuess.HCORE) D_engine = initial_density_closed_shell( system.unit_cell_molecule(), basis, n_occ, guess, is_periodic=True, periodic_system=system, lattice_opts=lat_opts_2e, # READ restart (Γ-only): prior g=0 cell density (pre-resolved from # read_from, or read + projected from read_path). Ignored unless READ. read_density=getattr(opts, "read_density", None), read_path=getattr(opts, "read_path", ""), ) if D_engine is not None: # --- Multi-k cross-cell density fix (v0.14.0) ------------------- # For n_k > 1 the per-k HCORE diagonalisation at line 619 already # gave C_per_k that vary with k, so D_real from the per-k fold # (line 640) carries physically correct P(g!=0) blocks that restore # the image-cell AO overlap on the DFT grid (∫rdr -> N_elec ≈ 20 # instead of ~18.95). Without this fix, P(g!=0) = 0 on the first # iteration makes r(r) systematically ~5 % too low on dense # crystals (MgO, NaCl, ...), the XC potential V_xc is too weak, # and the SCF converges ~400 mHa above the correct stationary # point -- functional-independent (LDA / PBE / r^2SCAN tested). # # For multi-k we keep the per-k density in full (g=0 + g!=0) rather # than injecting just the g!=0 blocks from the fold while keeping # SAD at g=0 -- the mixed density is not idempotent under the Bloch # fold and the inconsistent cross-cell charge causes Fock-overshoot # at iteration 2. The per-k HCORE g=0 block is a slightly worse # guess than SAD but the benefit of correct cross-cell r(r) # dominates on dense crystals (the SCF descends correctly from # iteration 1 instead of moving upward). # # Γ-only and n_k == 1 are unaffected -- P(g!=0) = 0 is physically # correct there. Tracked by the parity ladder: # examples/regression/crystal_parity/parity_mgo_{svwn,pbe,r2scan}_sto3g.py # --------------------------------------------------------------- if n_k > 1: # Multi-k: keep the full per-k density (with proper P(g!=0)). # Replacing only g=0 with SAD while keeping HCORE g!=0 blocks # produces an inconsistent density set -- the mixed g=0 and # g!=0 blocks are not idempotent under the Bloch fold and # cause iteration-2 Fock overshoot. Using the per-k density # in full (including its g=0 block) gives a slightly worse # initial home-cell guess but the correct cross-cell charge # and idempotency mean the SCF descends monotonically from # iteration 1. plog.info( f"initial guess: {guess.name} (multi-k: per-k density " f"with Hcore-diag cross-cell blocks -- ∫rdr restored)" ) # D_real already carries the per-k density; skip the overwrite. else: plog.info(f"initial guess: {guess.name} (g=0 density from GuessEngine)") for g_idx in range(len(D_real.cells)): if (D_real.cells[g_idx].index == np.array([0, 0, 0])).all(): D_real.set_block(g_idx, D_engine) else: D_real.set_block( g_idx, np.zeros_like(D_engine, dtype=float), ) else: plog.info(f"initial guess: {guess.name} (Hcore-diag per k)") initial_density_is_local = D_engine is not None density_from_c_per_k = not initial_density_is_local D_real_prev: Optional[LatticeMatrixSet] = None # ---- SCF aids ---------------------------------------------------- damping = float(opts.damping) if not (0.0 <= damping < 1.0): raise ValueError( f"run_pbc_bipole_rks: 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[MultiKPeriodicSCFAccelerator] = ( MultiKPeriodicSCFAccelerator(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; " f"got {type(level_shift_schedule).__name__}" ) # CRYSTAL-style FMIXING (same convention as RHF BIPOLE driver). # 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_k_prev_mixed: Optional[List[np.ndarray]] = None if use_mom: plog.info("MOM: ON") C_prev_occ_per_k: Optional[List[np.ndarray]] = 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 l_max = {oda_trust_lambda_max})") # ---- Ewald J-split cache ----------------------------------------- j_lr_cache = v_ne_lr_cache if use_ewald_j_split and not use_exact_ewald_j_for_pure_rks: if system.dim != 3: raise ValueError("use_ewald_j_split requires dim=3") if 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 " "full-mesh weights or IBZ-reduced mesh with ir_mapping" ) from .bipole_fock_ewald import _build_j_long_range_cache assert omega_used is not None if _pair_mode: # M3: the J^LR blocks must land on the pair-resolved output # template; dedicated cache (never the radial V_ne one). with plog.stage( "j_lr_cache", detail=( f"Ewald long-range J kernel on the pair-resolved " f"template (K_max={ewald_k_max} bohr^-1)" ), ): 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, ) cells_r_cart_arr = np.array( [np.asarray(c.r_cart, dtype=float) for c in cells], dtype=float, ) if j_lr_cache is None: # The reciprocal-space Ewald long-range J kernel precompute is # one of the heaviest silent pre-SCF stages (can be many # minutes on a tight lattice / large K_max). Bracket it so a # stalled job shows ``[j_lr_cache]`` as its last live line. with plog.stage( "j_lr_cache", detail=f"Ewald long-range J kernel (K_max={ewald_k_max} bohr^-1)", ): 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 LR exchange # (hybrids only -- pure functionals carry no HF exchange). Shares # the J^LR cache's Ewald w and K_max envelope. x_lr_cache = None if exchange_split_active and n_k > 1 and alpha_hf > 0.0: 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 # Per-(k,k') q-channel exchange tables: O(n_k^2) channels, the # heaviest multi-k hybrid setup stage -- bracket for localization. with plog.stage( "k_lr_cache", detail=f"{n_k} q-channels, K_max={ewald_k_max} bohr^-1", ): 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"(a_HF = {alpha_hf:g})" ) # Incremental/differential J_SR(+K_SR) accumulator (opt-in; see # ``resolve_incremental_jk``). One accumulator on the total density: # hybrids build J_SR+K_SR (build_jk), pure functionals build J_SR only # (build_fock, K=None in the shim). incremental_jk = resolve_incremental_jk( use_incremental_fock=use_incremental_fock, exchange_split_active=exchange_split_active, use_oda=use_oda, plog=plog, ) def _build_fock_for_density( density: LatticeMatrixSet, *, coeffs_for_rho: Optional[Sequence[np.ndarray]], use_incremental: bool = True, ) -> _PBCBipoleRKSFockBuild: """Build F^2e(g), add V_xc, and assemble F(k).""" fb = build_bipole_restricted_fock( _fock_ctx, density, coeffs_for_rho=coeffs_for_rho, alpha_hf=alpha_hf, exchange_assembly=exx, use_incremental=use_incremental, ) f2e_real = fb.f2e_real K_corr_per_k = fb.k_corr_per_k # ---- Build XC potential on the DFT grid ---------------------- D_xc_set = _density_set_gamma_or_lattice(S_lat, density) xc_result = build_xc_periodic( basis, system, grid, func, D_xc_set, lat_opts_2e, ) # ---- Assemble per-k Fock matrices ---------------------------- f_k_list: List[np.ndarray] = [] F2e_k_all = _bloch_sum_blocks_multi_k( f2e_real.blocks, f2e_real.cells, k_points, ) for k_idx, k in enumerate(k_points): k_arr = np.asarray(k, dtype=float) Vxc_k = np.asarray(bloch_sum(xc_result.V_xc, k_arr)) F_k = ( F2e_k_all[k_idx] + Vxc_k + np.asarray(Hcore_k_list[k_idx], dtype=complex) ) if K_corr_per_k is not None: # Ewald exchange split: a_HF.(K_LR + G=0) per k (a # single Γ entry at n_k = 1). F_k = F_k - 0.5 * K_corr_per_k[k_idx] F_k = 0.5 * (F_k + F_k.conj().T) f_k_list.append(F_k) return _PBCBipoleRKSFockBuild( f2e_real=f2e_real, f_k_list=f_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=float(xc_result.e_xc), screened_exchange_execution=fb.screened_exchange_execution, output_cell_farming_execution=( fb.output_cell_farming_execution ), ) # ---- Retired multipole far-field config ----------------------------- from .bipole_fock_multipole import ( # noqa: E402 BipoleMultipoleConfig, resolve_multipole_config, ) # Explicit requests fail before setup. Keep a disabled config here for # the shared Fock context until the research-only implementation is # removed from that internal API. _ff_enable: Optional[bool] = False _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 quartet-level far-field 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 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 restricted Fock-build context (M2 unification) ---------- # The RKS wrapper adds V_xc after the shared two-electron builder returns. # _build_fock_for_density (above) references this via late binding; it is # only called from the SCF loop below, after this point. _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=incremental_jk, 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_occ, plog=plog, sr_image_extent=_sr_image_extent, exact_zone_bohr=_exact_zone, exact_j_for_pure_rks=use_exact_ewald_j_for_pure_rks, exact_j_ke_cutoff=exact_j_ke_cutoff, exact_j_chunk_size=exact_j_chunk_size, output_cell_farming_task_kind=( output_cell_farming_task_kind if farm_output_cells else None ), output_cell_farming_strategy=output_cell_farming_strategy, ) def _split_k_density_list(density: LatticeMatrixSet) -> List[np.ndarray]: return split_k_density_list(_fock_ctx, density) plog.banner("SCF (PBC BIPOLE RKS, direct-space)") plog.info(" iter energy (Ha) dE ||[F,DS]|| DIIS") scf_trace: List[SCFIteration] = [] energy_components: List[PBCBipoleEnergyComponents] = [] E_prev = 0.0 F_k_list: List[np.ndarray] = [np.zeros_like(H) for H in Hcore_k_list] E_elec = 0.0 e_xc = 0.0 e_dft_plus_u = 0.0 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[_PBCBipoleRKSFockBuild] = None # ---- DFT+U setup (closed-shell BIPOLE RKS +U) ------------------------ 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_rks: 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: LatticeMatrixSet, fock_k_list: List[np.ndarray], ) -> float: """Apply +U energy/potential 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: P_k_all = _split_k_density_list(density) else: P_k_all = _bloch_sum_blocks_multi_k( density.blocks, density.cells, k_points ) P_sigma_k_for_u = [ 0.25 * (P_k + P_k.conj().T) for P_k in P_k_all ] e_sigma, v_ao = _compute_dft_plus_u_multi_k_per_spin_cxx( dft_plus_u_sites_cxx, dft_plus_u_ao_groups, S_k_list, P_sigma_k_for_u, list(weights), ) v_ao = np.asarray(v_ao, dtype=complex) for k_idx, S_k in enumerate(S_k_list): fock = fock_k_list[k_idx] + S_k @ v_ao @ S_k fock_k_list[k_idx] = 0.5 * (fock + fock.conj().T) return 2.0 * float(e_sigma) for iter_idx in range(1, int(opts.max_iter) + 1): if damper is not None: damping = damper.alpha diis_active = use_diis and iter_idx >= diis_start_iter D_used = D_real if iter_idx > 1 and damping > 0.0 and not diis_active: D_used = _damp_lattice_matrix(D_real, D_real_prev, damping) 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_used, coeffs_for_rho=(C_per_k if d_used_from_coeffs else None), ) F2e_real = fock_build.f2e_real F_k_list = fock_build.f_k_list # ---- DFT+U: per-spin per-k Fock contribution (closed-shell). # Same pattern as run_pbc_bipole_rhf -- closed-shell uses # P_s = P_total/2 and E_U_total = 2 x E_s. e_dft_plus_u = _apply_dft_plus_u(D_used, F_k_list) # ---- XC energy ----------------------------------------------- # From the SAME quadrature that produced this iteration's V_xc # (inside _build_fock_for_density on D_used) -- the loop used to # run a second, redundant build_xc_periodic here every iteration # just to extract e_xc. assert fock_build.e_xc is not None e_xc = float(fock_build.e_xc) # ---- Energy -------------------------------------------------- E_kin = _lattice_contract(D_used, T_lat, operator_name="T") E_ne = _lattice_contract(D_used, V_lat, operator_name="V_ne") E_2e = ( 0.5 * _lattice_contract( D_used, F2e_real, operator_name="F2e", ) # k-space exchange correction (Ewald exchange split). + fock_build.e_2e_k_correction ) E_elec = E_kin + E_ne + E_2e + e_xc grad_norm_sum = 0.0 error_k_list: List[np.ndarray] = [] D_k_list: List[np.ndarray] = [] D_k_split_guess: Optional[List[np.ndarray]] = None if exchange_split_active and initial_density_is_local and iter_idx == 1: # BvK representative for local AND Bloch warm-start storage # (home block at Γ; exact torus fold at multi-k -- S_g over # the unprojected fold would overcount). D_k_split_guess = _split_k_density_list(D_used) D_k_guess_fold: Optional[List[np.ndarray]] = None if ( initial_density_is_local and iter_idx == 1 and D_k_split_guess is None ): D_k_guess_fold = _bloch_sum_blocks_multi_k( D_used.blocks, D_used.cells, k_points ) for idx in range(n_k): if initial_density_is_local and iter_idx == 1: if D_k_split_guess is not None: D_k = D_k_split_guess[idx] else: assert D_k_guess_fold is not None D_k = D_k_guess_fold[idx] D_k = 0.5 * (D_k + D_k.conj().T) else: C_k = C_per_k[idx] if _occupations_are_per_k_integer_aufbau(occ_per_k, n_occ): C_occ = C_k[:, :n_occ] D_k = 2.0 * (C_occ @ C_occ.conj().T) else: # Fractional-occupation density: D(k) = S_i n_i C_i C_i+ occ = np.asarray(occ_per_k[idx], dtype=float) C_full = np.asarray(C_k, dtype=np.complex128) D_k = (C_full * occ[None, :]) @ C_full.conj().T D_k_list.append(D_k) F_k = F_k_list[idx] w = float(weights[idx]) S_k = S_k_list[idx] FDS = F_k @ D_k @ S_k grad = FDS - FDS.conj().T error_k_list.append(grad) grad_norm_sum += w * float(np.linalg.norm(grad)) E_total = float(E_elec) + e_nuc + e_dft_plus_u # EXT EL-SPHEROPOLE -- a 3D-Ewald-gauge correction, identically # zero in the direct (non-Ewald) gauge used for dim<3, and # OMITTED under the corrected gauge (double-count -- see the # RHF driver note). if system.dim == 3 and not exchange_split_active: E_sphero = compute_ext_el_spheropole(D_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_rks", iter_idx, free_energy, grad_norm_sum, dE, ) scf_trace.append( SCFIteration( iter=iter_idx, energy=float(free_energy), delta_e=float(dE if iter_idx > 1 else 0.0), grad_norm=float(grad_norm_sum), diis_subspace=(accel.subspace_size if accel is not None else 0), ) ) plog.iteration( iter_idx, energy=float(free_energy), dE=float(dE if iter_idx > 1 else 0.0), grad=float(grad_norm_sum), diis=(accel.subspace_size if accel is not None else 0), ) 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_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), ) physical_fock_stationary = ( grad_norm_sum < float(opts.conv_tol_grad) ) converged = ( iter_idx > 1 and abs(dE) < float(opts.conv_tol_energy) and physical_fock_stationary ) # SCF-accelerator extrapolation. Full # {DIIS, KDIIS, EDIIS, EDIIS_DIIS, ADIIS} family wired here; # bridged modes route through the M2e stacked-real-block bridge # (see ``per_k_to_stacked_real_blocks`` in # ``periodic_scf_accelerators.py``). if accel is not None: if exchange_split_active: # Unprojected fold: BvK representative per k (home # block at Γ; exact torus fold at multi-k). density_k_list = _split_k_density_list(D_used) else: density_k_list = _bloch_sum_blocks_multi_k( D_used.blocks, D_used.cells, k_points ) F_ex_list = accel.extrapolate_rhf( F_k_list, error_k_list=error_k_list, density_k_list=density_k_list, energy=free_energy, mo_coeffs_k_list=C_per_k, n_occ=n_occ, weights=list(weights), cells=cells, kpoints=list(k_points), ) # Once the physical Fock F(D) commutes with D, diagonalise that # Fock -- not the extrapolated one -- even if the lagging energy # difference still needs one confirmation iteration. Reapplying # DIIS at a stationary density can kick the SCF away before the # energy test catches up; a near-machine-zero error history also # makes the Pulay B-matrix singular. Fractional occupations still # pass through the density fixed-point check below after this # physical-Fock update. See the RHF twin in pbc_bipole.py and # tests/test_pbc_bipole_diis_converged_basin.py. if diis_active and not physical_fock_stationary: F_k_list = F_ex_list # --- FMIXING (CRYSTAL-style, after DIIS, before level-shift) # Skipped once the physical Fock is stationary (see DIIS note above). if fock_mixing_value != 0.0 and not physical_fock_stationary: if F_k_prev_mixed is not None: F_mixed_list: List[np.ndarray] = [] for idx in range(n_k): F_mixed = (1.0 - fock_mixing_value) * F_k_list[ idx ] + fock_mixing_value * F_k_prev_mixed[idx] F_mixed = 0.5 * (F_mixed + F_mixed.conj().T) F_mixed_list.append(F_mixed) F_k_list = F_mixed_list F_k_prev_mixed = [np.asarray(F, dtype=complex).copy() for F in F_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 physical_fock_stationary: F_for_diag: List[np.ndarray] = [] for idx in range(n_k): D_k = D_k_list[idx] S_k = S_k_list[idx] F_shift = ( F_k_list[idx] + level_shift_b * S_k - (level_shift_b / 2.0) * (S_k @ D_k @ S_k) ) F_shift = 0.5 * (F_shift + F_shift.conj().T) F_for_diag.append(F_shift) else: F_for_diag = F_k_list # Diagonalise new_C_per_k = [] new_eps_per_k = [] for idx in range(n_k): C_k, eps_k = _diag_in_orth_basis( F_for_diag[idx], X_k_list[idx], ) new_C_per_k.append(C_k) new_eps_per_k.append(eps_k) # MOM if use_mom and C_prev_occ_per_k is not None: for idx in range(n_k): C_k = new_C_per_k[idx] eps_k = new_eps_per_k[idx] S_k = S_k_list[idx] sel = _mom_select( C_k, S_k, C_prev_occ_per_k[idx], n_occ, 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]) new_C_per_k[idx] = C_k[:, order] new_eps_per_k[idx] = eps_k[order] C_per_k = new_C_per_k eps_per_k = new_eps_per_k occ_per_k, fermi_level, entropy = _occupations_from_eps(eps_per_k) _fractional_occupations_here = _fractional_density_needed(occ_per_k) if _fractional_occupations_here: D_real_new = real_space_density_from_kpoints_fractional( C_per_k, occ_per_k, kmesh, cells_density, ) else: D_real_new = real_space_density_from_kpoints( C_per_k, [n_occ] * n_k, kmesh, cells_density, ) # Corrected gauge: the full Bloch fold IS the density the # builders need (see run_pbc_bipole_rhf); legacy keeps the # Γ-locality projection. if not exchange_split_active: _zero_cross_cell_density(D_real_new, basis.nbasis, n_k) # Require the newly diagonalised density to be the same fixed point as # D_used before accepting convergence. This also catches the # occupation-only motion that a finite-temperature commutator cannot # see. if converged: density_fixed_point_residual = max( ( float( np.max( np.abs( np.asarray(new_block) - np.asarray(old_block) ) ) ) for new_block, old_block in zip( D_real_new.blocks, D_used.blocks ) ), default=0.0, ) converged = density_fixed_point_residual < float( opts.conv_tol_grad ) # ODA if use_oda: fock_naive = _build_fock_for_density( D_real_new, coeffs_for_rho=C_per_k, use_incremental=False, # off the per-iter ΔD chain ) oda_step = _compute_oda_lambda( D_used, D_real_new, F_k_list, fock_naive.f_k_list, [np.asarray(k) for k in k_points], weights, trust_lambda_max=oda_trust_lambda_max, ) _oda_mix(D_used, D_real_new, oda_step.lam) D_real_prev = D_real D_real = D_used density_from_c_per_k = oda_step.lam == 1.0 plog.info(f" ODA: l = {oda_step.lam:.4f}") else: D_real_prev = D_used D_real = D_real_new density_from_c_per_k = True if use_mom: C_prev_occ_per_k = [ np.asarray(C_per_k[idx][:, :n_occ]).copy() 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. The loop's gate measured F(D_prev) # on D_prev; at a marginal fixed point the true commutator # F(D_new) on D_new can still sit above the gate by one # iteration's step, and the post-loop terminal check would then # revoke the convergence with no way back. Confirming here lets # the loop run the extra iteration(s) it needs; the rebuild is # reused by the post-loop finalisation, so healthy rows pay # nothing extra. _confirm_fb = _build_fock_for_density( D_real, coeffs_for_rho=(C_per_k if density_from_c_per_k else None), use_incremental=False, ) _confirm_grad = restricted_bipole_commutator_norm( _confirm_fb.f_k_list, ( _split_k_density_list(D_real) if exchange_split_active else _bloch_sum_blocks_multi_k( D_real.blocks, D_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 # ---- Ionic-Γ basin-health diagnostic (smearing straddle) ----------- # Surface (don't bury, Sec.7) the case where finite-T smearing washes # out a small (often minimal-basis-underestimated) gap and selects a # near-metallic basin hundreds of mHa off the physical solution. basin_warning = smearing_basin_warning( smearing_T, [(eps_per_k, occ_per_k, n_occ, 2.0)], entropy, "run_pbc_bipole_rks", ) 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 # final diagonalisation commits a new density even on max-iteration # exhaustion, so this rebuild is required for both success and failure. 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_real, coeffs_for_rho=(C_per_k if density_from_c_per_k else None), use_incremental=False, ) ) F_k_list = _fb.f_k_list e_dft_plus_u = _apply_dft_plus_u(D_real, F_k_list) screened_exchange_execution = _fb.screened_exchange_execution D_xc_set = _density_set_gamma_or_lattice(S_lat, D_real) _xc = build_xc_periodic( basis, system, grid, func, D_xc_set, lat_opts, ) E_kin_f = _lattice_contract(D_real, T_lat, operator_name="T") E_ne_f = _lattice_contract(D_real, V_lat, operator_name="V_ne") E_2e_f = ( 0.5 * _lattice_contract(D_real, _fb.f2e_real, operator_name="F2e") + _fb.e_2e_k_correction ) 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, and omitted # under the corrected gauge). if system.dim == 3 and not exchange_split_active: E_sphero_final = compute_ext_el_spheropole(D_real, 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), ) free_energy_final = E_total - smearing_T * entropy final_grad_norm = restricted_bipole_commutator_norm( F_k_list, ( _split_k_density_list(D_real) if exchange_split_active else _bloch_sum_blocks_multi_k( D_real.blocks, D_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 PBCBipoleRKSResult( 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, mo_energies=eps_per_k, mo_coeffs=C_per_k, fock=F_k_list, overlap=S_k_list, hcore=Hcore_k_list, density=D_real, 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, functional=str(opts.functional), smearing_temperature=smearing_T, fermi_level=float(fermi_level), entropy=float(entropy), free_energy=float(free_energy_final), occupations=[np.asarray(o, dtype=float) for o in occ_per_k], 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, output_cell_farming_execution=( _fb.output_cell_farming_execution ), screened_exchange_execution=screened_exchange_execution, basin_warning=basin_warning, 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, )