Python API reference

Autogenerated from the docstrings on the vibe-qc Python module. Fall back to the source for anything not yet documented inline.

Molecular

vibeqc.Atom
vibeqc.Molecule
vibeqc.BasisSet
vibeqc.ShellInfo
vibeqc.from_xyz	Parse an XYZ file (positions in Ångström).
vibeqc.RHFOptions
vibeqc.RHFResult
vibeqc.run_rhf	Restricted Hartree-Fock SCF on a closed-shell molecule.
vibeqc.UHFOptions
vibeqc.UHFResult
vibeqc.run_uhf	Unrestricted Hartree-Fock SCF on an open-shell molecule.
vibeqc.RKSOptions
vibeqc.RKSResult
vibeqc.run_rks	Restricted Kohn-Sham SCF on a closed-shell molecule.
vibeqc.UKSOptions
vibeqc.UKSResult
vibeqc.run_uks	Unrestricted Kohn-Sham SCF on an open-shell molecule.
vibeqc.MP2Result
vibeqc.run_mp2
vibeqc.UMP2Result
vibeqc.run_ump2
vibeqc.CCSDOptions	Python-friendly CCSD option struct with aux-basis autodetection.
vibeqc.CCSDResult
vibeqc.CCSDIteration
vibeqc.run_ccsd	Run closed-shell CCSD (and optionally CCSD(T)).
vibeqc.chemical_core_orbital_count	Number of chemical-core spatial orbitals for frozen-core CCSD.
vibeqc.CC3Options	Controls for the dense ground-state CC3 iteration.
vibeqc.CC3Result	Result of a dense ground-state CC3 calculation.
vibeqc.CC3Iteration	One CC3 T1/T2 iteration.
vibeqc.cc3	Solve ground-state CC3 for a canonical closed-shell reference.

Input / output workflow

High-level “run a job” driver plus external-format writers.

vibeqc.run_job	Run a vibe-qc SCF job and write the standard output files.
vibeqc.write_molden	Write geometry, basis, and molecular orbitals to a Molden-format file.
vibeqc.write_orca_hess	Write a vibe-qc HessianResult to an ORCA-format .hess file.
vibeqc.write_xyz_trajectory	Write a sequence of Molecule frames as a multi-XYZ trajectory file.
vibeqc.write_opt_trajectory	Write a geometry-optimization history as a multi-XYZ trajectory with per-step energies on the comment line.
vibeqc.normal_mode_trajectory	Generate a list of Molecule frames sampling one vibrational normal mode for animated visualization.
vibeqc.format_scf_trace	Return a multi-line string with a header, per-iteration lines and a summary.
vibeqc.log_scf_trace	Emit the SCF trace through the logging module.

The trajectory trio above (Phase M2) writes the multi-XYZ format that moltui, ASE, OVITO, Avogadro, and PyMOL all read directly:

• :func:vibeqc.write_xyz_trajectory, generic multi-frame writer.

• :func:vibeqc.write_opt_trajectory, geometry-optimization history with auto-formatted comment lines ("step N  E = …  |grad| = …"). Default extension .opt by ORCA-style convention; on-disk format is identical to a plain multi-XYZ.

• :func:vibeqc.normal_mode_trajectory, discretise one vibrational mode into n_frames displaced geometries for an animated normal-mode movie. Pair with :func:~vibeqc.write_xyz_trajectory.

Integrals, basis, XC

vibeqc.compute_overlap
vibeqc.compute_kinetic
vibeqc.compute_nuclear
vibeqc.compute_eri
vibeqc.compute_gradient	RHF analytic nuclear gradient (Ha/bohr, per atom).
vibeqc.compute_gradient_uhf	UHF analytic nuclear gradient (Ha/bohr, per atom).
vibeqc.compute_gradient_rks	RKS analytic nuclear gradient (Ha/bohr, per atom).
vibeqc.compute_gradient_uks	UKS analytic nuclear gradient (Ha/bohr, per atom).
vibeqc.Functional
vibeqc.XCKind
vibeqc.build_grid
vibeqc.Grid
vibeqc.GridOptions
vibeqc.evaluate_ao
vibeqc.evaluate_ao_with_gradient

Periodic

vibeqc.PeriodicSystem
vibeqc.LatticeCell
vibeqc.LatticeMatrixSet
vibeqc.LatticeSumOptions
vibeqc.CoulombMethod
vibeqc.BlochKMesh
vibeqc.BandDiag
vibeqc.direct_lattice_cells
vibeqc.bloch_sum
vibeqc.monkhorst_pack	Build a legacy BlochKMesh Monkhorst-Pack mesh.
vibeqc.diagonalize_bloch
vibeqc.compute_overlap_lattice
vibeqc.compute_kinetic_lattice
vibeqc.compute_nuclear_lattice
vibeqc.nuclear_repulsion_per_cell
vibeqc.compute_nuclear_erfc_lattice
vibeqc.EwaldOptions
vibeqc.ewald_point_charge_energy
vibeqc.ewald_nuclear_repulsion
vibeqc.build_jk_gamma_molecular_limit
vibeqc.build_fock_2e_real_space
vibeqc.build_xc_periodic
vibeqc.real_space_density_from_kpoints
vibeqc.PeriodicRHFOptions
vibeqc.PeriodicRHFResult
vibeqc.run_rhf_periodic_gamma	Γ-only closed-shell RHF for a periodic system (molecular-limit regime).
vibeqc.PeriodicSCFOptions
vibeqc.run_rhf_periodic
vibeqc.PeriodicKSOptions
vibeqc.PeriodicKSResult
vibeqc.run_rks_periodic	Multi-k closed-shell periodic Kohn-Sham SCF (DIRECT_TRUNCATED).
vibeqc.AtomicRadialGrid	Per-atom radial x Lebedev quadrature grid.
vibeqc.default_alpha_for_element	Mura-Knowles radial scale a (bohr) for element Z.
vibeqc.lebedev_supported_orders	Return the Lebedev orders scipy.integrate.lebedev_rule supports.

The AtomicRadialGrid family (per-atom Mura-Knowles radial × Lebedev-Laikov angular quadrature) is the M3b-aug-A infrastructure for GAPW augmentation. Not yet wired into the SCF, see gapw.md for the user- facing surface and vibeqc.periodic_gapw_atomic_grid for the module-level entry.

Crystal / symmetry

vibeqc.Crystal
vibeqc.SpaceGroup
vibeqc.SymmetryOp
vibeqc.IrreducibleKMesh
vibeqc.SymmetriseReport	Metadata describing a periodic-structure symmetrisation.
vibeqc.SymmetriseResult	Return value of symmetrise().
vibeqc.SymmetrisedOrbitIntegralResult	Result bundle for GS3 standardise-then-compress helpers.
vibeqc.analyze_symmetry
vibeqc.attach_symmetry
vibeqc.detect_spacegroup	Return spglib's space-group analysis without mutating system.
vibeqc.symmetrise	Standardise and idealise a 3D periodic structure via spglib.
vibeqc.to_primitive
vibeqc.irreducible_kpoints
vibeqc.compute_overlap_lattice_symmetrised_with_orbits	Standardise system and build orbit-compressed overlap S(g).
vibeqc.compute_kinetic_lattice_symmetrised_with_orbits	Standardise system and build orbit-compressed kinetic T(g).
vibeqc.compute_nuclear_lattice_symmetrised_with_orbits	Standardise system and build orbit-compressed nuclear V(g).
vibeqc.read_cif	Parse a CIF file into a Crystal.
vibeqc.read_poscar	Parse a VASP 5 POSCAR/CONTCAR file into a Crystal.
vibeqc.write_poscar	Write a Crystal to VASP 5 POSCAR (Direct coordinates, Å lattice).
vibeqc.spglib_version

Properties

vibeqc.mulliken_charges	Mulliken atomic partial charges q_A = Z_A - S_{mu in A} (P.S)_mumu.
vibeqc.loewdin_charges	Atom-block Löwdin atomic partial charges.
vibeqc.mayer_bond_orders	Mayer bond-order matrix, shape (n_atoms, n_atoms).
vibeqc.dipole_moment	Electric dipole moment of a converged SCF calculation.
vibeqc.DipoleMoment	Dipole moment components in atomic units (e.bohr), plus Debye.
vibeqc.center_of_mass	Center of mass (bohr).
vibeqc.compute_dipole
vibeqc.DipoleIntegrals

Live progress, runtime manifest, and perf log

Observability surface: defeats output buffering on long runs, pins the runtime environment alongside every job, writes a post-mortem perf breakdown when opted in, exposes a verbosity knob plus a stdlib logging adapter, writes a machine-readable NDJSON convergence log, writes a crash dump on SCF failure, and records the external-program validation boundary in the .system manifest.

run_job accepts verbose: int = None (PySCF-convention 0..9; None reads $VIBEQC_VERBOSE, default 4) and use_logging: bool = False (route emits through logging.getLogger("vibeqc.run_job"), banners + milestones land at INFO, per-iter SCF rows at DEBUG, warnings at WARNING). The same verbose= kwarg is threaded through every periodic SCF entry point (run_rhf_periodic_gamma_ewald3d, run_rks_periodic_multi_k_ewald3d, …) so direct callers of the lower-level drivers can dial verbosity without going through run_job. See docs/user_guide/output_files.md § “Verbosity” for the level table.

vibeqc.ProgressLogger	Per-stage progress emitter for long-running calculations.
vibeqc.resolve_progress	Normalize the progress= argument every SCF entry point takes.
vibeqc.system_info	Collect the runtime environment as a nested dict.
vibeqc.write_system_manifest	Write the per-job system manifest next to out_path.
vibeqc.PerfTracker	Accumulator for per-phase wall/CPU timings, per-iteration SCF rows, and memory snapshots over the course of a calculation.
vibeqc.PerfScope	Context manager that times its body and pushes the wall + CPU delta into the currently active PerfTracker.
vibeqc.perf_log	Activate a fresh PerfTracker for the duration of the block; write the formatted report to path on exit.
vibeqc.active_tracker	The currently active PerfTracker, or None if no perf_log() block is open.
vibeqc.format_perf_report	Render tracker as the on-disk perf report text.
vibeqc.StructuredLog	One-record-per-line NDJSON writer with line-flushed I/O.
vibeqc.structured_log	Activate a fresh StructuredLog for the duration of the block; close on exit.
vibeqc.active_structured_log	The currently active StructuredLog, or None if no structured_log() block is open.
vibeqc.run_fingerprint	A short hex digest summarizing a job's identifying inputs.
vibeqc.dump_on_failure	Write {out_stem}.dump (TOML) plus binary attachments capturing the last known SCF state.
vibeqc.load_dump	Parse a .dump TOML file and load its sibling .npy attachments.
vibeqc.classify_failure	Return a one-line likely_cause string for the dump's [hint] section.
vibeqc.crash_dump_context	Register a crash-dump stem for the duration of the block.

ProgressLogger is wired into every periodic SCF entry point (and into run_job); system_info() / write_system_manifest() are the public hooks for users driving the SCF drivers directly without run_job. perf_log() is the context-manager entry point for post-mortem perf logging, paired with PerfScope for instrumenting custom code. structured_log() is the v0.6 NDJSON entry point, one JSON record per SCF transition, format-stable, jq-friendly. dump_on_failure() / load_dump() are the v0.6 crash-dump pair: a snapshot on disk when an SCF fails ungracefully, round-trippable via load_dump() for bit-for-bit failure reproduction. See docs/user_guide/output_files.md for the user-facing walkthrough.

Memory budget

vibeqc.MemoryEstimate	Peak memory estimate for a calculation.
vibeqc.InsufficientMemoryError	Raised by check_memory when the estimate exceeds available RAM and the caller did not request an override.
vibeqc.estimate_memory	Peak memory estimate for method.
vibeqc.check_memory	Abort if estimate.total_bytes > available and allow_exceed is false.
vibeqc.available_memory_bytes	Best-effort available-RAM probe.
vibeqc.format_memory_report	One-stop formatter for the run_job output block.

Version & banner

vibeqc.VIBEQC_VERSION	str(object='') -> str str(bytes_or_buffer[, encoding[, errors]]) -> str
vibeqc.banner	Return the full banner as a single string, no trailing newline.
vibeqc.print_banner	Print the banner to file (default: stdout).
vibeqc.library_versions	Return the version strings of vibe-qc itself and its native dependencies.
vibeqc.libint_version
vibeqc.libxc_version
vibeqc.spglib_version

Basis-set utilities

vibeqc.basis_crystal

CRYSTAL-format basis-set parser and NWChem/.g94 emitter.

Bands, DOS, plotting

vibeqc.KPath	A discretised k-path -- sequence of k-points with cumulative arc length (for the x-axis when plotting) and labeled high-symmetry points (for the x-axis tick marks).
vibeqc.BandStructure	Eigenvalues at every k along a path.
vibeqc.DensityOfStates	Total density of states.
vibeqc.kpath_from_segments	Stitch a piecewise-linear k-path through high-symmetry points.
vibeqc.band_structure	Sample a real-space Fock matrix along a k-path.
vibeqc.band_structure_hcore	Non-interacting (Hcore) band structure: eigenvalues of T + V at every k-point.
vibeqc.density_of_states	Total DOS computed by Gaussian-broadening every eigenvalue of F(k) over kmesh onto an energy grid.
vibeqc.density_of_states_hcore	Non-interacting DOS for a system on a Monkhorst-Pack mesh.
vibeqc.plot.band_structure_figure	Draw a band-structure plot.
vibeqc.plot.dos_figure	Draw a density-of-states plot.
vibeqc.plot.bands_dos_figure	Combined band structure + DOS panel -- the standard solid-state layout (bands on the left with shared y-axis to a horizontal DOS on the right).

Volumetric output

vibeqc.CubeGrid	Uniform axis-aligned grid in bohr.
vibeqc.make_uniform_grid	Wrap an axis-aligned box around the molecule with padding bohr of headroom and a cubic voxel of spacing bohr.
vibeqc.write_cube_density	Write the total electron density r(r) = <D, chi⊗chi> to a Gaussian cube file.
vibeqc.write_cube_mo	Write a single molecular orbital phi_index(r) to a cube file.
vibeqc.write_cube_mos	Write a stack of MOs in a single multi-value cube file.
vibeqc.write_xsf_structure	Write a structure-only XSF file.
vibeqc.write_xsf_volume	Write a periodic XSF file with a single 3D scalar grid.
vibeqc.write_bxsf	Write a BXSF file (band XSF) for Fermi-surface visualization in XCrySDen.

SCF accelerators + initial guess

vibeqc.SCFAccelerator
vibeqc.InitialGuess
vibeqc.ADIIS
vibeqc.EDIIS
vibeqc.SCFMode
vibeqc.NewtonOptions
vibeqc.SOSCFOptions
vibeqc.SmearingOptions	Canonical user-facing smearing configuration.

Wavefunction methods (non-mean-field solvers)

The vibeqc.solvers family: Full CI, Selected CI, DMRG, variational 2-RDM, and the transcorrelated Hamiltonian.

vibeqc.Hamiltonian	One- and two-electron integrals in an orthonormal spatial-orbital basis.
vibeqc.solve_selected_ci	One-shot Selected-CI solve.
vibeqc.SelectedCIOptions	Options for the Selected-CI solver.
vibeqc.solve_dmrg
vibeqc.DMRGOptions	Options for the DMRG solver.
vibeqc.solve_v2rdm	One-shot v2RDM solve.
vibeqc.V2RDMOptions	Options for the v2RDM solver.
vibeqc.build_transcorrelated_hamiltonian	Apply the transcorrelated similarity transformation to a Hamiltonian.
vibeqc.TranscorrelatedOptions	Options for the transcorrelated Hamiltonian builder.
vibeqc.SolverResult	Common result container for all non-mean-field solvers.
vibeqc.CISDOptions	CISD options for run_job(method="cisd") / citype="cisd".
vibeqc.CISDResult	Result of a fixed-space CISD (or CIS, max_excitation=1).
vibeqc.cisd	Run fixed-space CISD on an MO-basis Hamiltonian.
vibeqc.solvers.generate_determinants	Generate all determinants for nalpha a + nbeta b electrons in norb orbitals.
vibeqc.solvers.build_hamiltonian_matrix_unrestricted	Build the full CI Hamiltonian matrix in the unrestricted determinant basis.
vibeqc.solvers.diagonal_matrix_element_unrestricted	<D|H|D> for an unrestricted determinant.
vibeqc.get_hf_orbital_provider	Run vibe-qc's RHF and return the MO coefficient matrix.
vibeqc.build_hamiltonian_mo	Build a Hamiltonian in the MO basis.
vibeqc.solvers.transform_hamiltonian	Transform a Hamiltonian into a new orthonormal basis given by C.

Composite methods (3c family) + double hybrids + range-separated hybrids

vibeqc.run_double_hybrid	Generic double-hybrid dispatcher.
vibeqc.DoubleHybridResult	Result of a double-hybrid run: the SCF (hybrid-DFT) result, the post-SCF MP2 correction result, optionally a dispersion correction, and the combined total energy.
vibeqc.run_wb97x_d	wB97X-D (Chai & Head-Gordon, *Phys.
vibeqc.WB97XDResult	Result of an wB97X-D run: the range-separated-hybrid SCF result, the Chai-Head-Gordon empirical dispersion correction, and the combined total energy.
vibeqc.ShortRangeCorrection	Canonical short-range bond (SRB) correction of the 3c stack.
vibeqc.MP2Options

Dispersion (D3 / D4 + counterpoise + EEQ)

vibeqc.compute_d3bj	Pairwise D3(BJ) dispersion energy (and optionally gradient).
vibeqc.compute_d4	D4 dispersion correction (Caldeweyher et al. 2019).
vibeqc.compute_chg_dispersion
vibeqc.compute_gcp	Geometric counterpoise correction (Kruse & Grimme 2012).
vibeqc.eeq_charges
vibeqc.DispersionResult
vibeqc.D4Result	Result of a compute_d4() call.
vibeqc.GCPResult	Return value of compute_gcp().
vibeqc.EEQResult
vibeqc.EEQOptions
vibeqc.PeriodicDispersionResult	Per-unit-cell dispersion energy plus optional gradient.

Implicit solvation (CPCM / COSMO)

vibeqc.CPCMResult	Outcome of one apparent-surface-charge solve.
vibeqc.SolventResult	Outcome of a CPCM-coupled SCF run.

Geometry optimization + Hessian

vibeqc.optimize_molecule	Relax molecular geometry using analytic gradients + L-BFGS-B.
vibeqc.MolecularOptimizeResult	Container for molecular geometry optimization results.
vibeqc.OptimizeResult	Container for optimization results.
vibeqc.HessianFDOptions	Knobs for compute_hessian_fd().
vibeqc.HessianResult	Output of compute_hessian_fd().
vibeqc.CPHFOptions	Knobs for cphf_solve_rhf().
vibeqc.NEBResult	Outcome of a run_neb() run.
vibeqc.ScanResult	Container for the output of relaxed_scan().

Periodic SCF (full driver matrix)

The Γ-only entry points already appear under “Periodic” above. The multi-k drivers, the BIPOLE family, and the Ewald and GDF variants land here.

χ-CCM[1] entries above cover the finite-translation-group character construction. Γ-CCM (aiccm2026dev-a) uses the separate union-and-weight/Wigner–Seitz integral-weighting construction. Γ-CCM’s module is vibeqc.periodic.ccm. Key entry points:

• vibeqc.periodic.ccm.CCMSystem - build the cyclic cluster

• vibeqc.periodic.ccm.scf.run_ccm_rhf / run_ccm_rhf_scalable - union-and-weight Γ-CCM HF

• vibeqc.periodic.ccm.dft.run_ccm_rks / run_ccm_uks - union-and-weight Γ-CCM KS-DFT

• vibeqc.periodic.ccm.ri.run_ccm_rhf_gdf / run_ccm_rks_gdf - neutral fitted-torus character/Bloch controls, not Γ-CCM construction identities

• vibeqc.periodic.ccm.direct.run_ccm_rhf_direct - real-Gamma evaluation of the same neutral fitted-torus control

• vibeqc.periodic.ccm.ri.run_ccm_rhf_rijcosx - WSSC RIJCOSX research route

• vibeqc.periodic.ccm.mp2.run_ccm_mp2 / vibeqc.periodic.ccm.ump2.run_ccm_ump2 - union-and-weight Γ-CCM MP2/UMP2 with method="aiccm2026dev-a"; passing a neutral cderi selects the separately declared control instead

• vibeqc.periodic.ccm.ccsd.run_ccm_ccsd - union-and-weight Γ-CCM CCSD(T) with method="aiccm2026dev-a"; its cderi route is the separate neutral fitted-torus control

• vibeqc.periodic.ccm.mp2.run_ccm_ri_mp2 / vibeqc.periodic.ccm.ccsd.run_ccm_ri_ccsd - one-call canonical correlation on the neutral fitted-torus control

• vibeqc.periodic.ccm.uccsd.run_ccm_uccsd - open-shell UCCSD(T) on the neutral fitted-torus control, not a Γ-CCM or χ-CCM construction API

• Properties: ccm_homo_lumo_gap, ccm_mulliken_charges, ccm_lowdin_charges, ccm_dipole, ccm_numerical_gradient

• Localization: localise_ccm, ccm_pao

• Neutral-control DLPNO: ccm_dlpno_mp2, ccm_dlpno_ccsd, ccm_dlpno_ump2, ccm_dlpno_uccsd. These correlation APIs use the neutral fitted-torus operator and are not assigned a Γ-CCM or χ-CCM identity.

• Neutral reference: ccm_eri_neutral, ccm_neutral_cderi

See the Γ-CCM reference for the construction/neutral-control API boundary and the full method inventory.

vibeqc.run_rhf_periodic_gamma_gdf	Run Γ-only closed-shell periodic RHF/RKS via native GDF.
vibeqc.run_krhf_periodic_gdf	Run closed-shell periodic HF / KS multi-k SCF via native GDF.
vibeqc.run_krks_periodic_gdf	Run closed-shell periodic KS-DFT multi-k SCF via native GDF.
vibeqc.run_aiccm2026dev_b_rhf	Minimise the finite-torus closed-shell RHF energy per cell.
vibeqc.run_aiccm2026dev_b_rks	Minimise the finite-torus closed-shell Kohn--Sham energy per cell.
vibeqc.run_aiccm2026dev_b_uhf	Minimize the finite-torus unrestricted Hartree--Fock functional.
vibeqc.run_aiccm2026dev_b_uks	Minimize the finite-torus spin-polarized Kohn--Sham functional.
vibeqc.run_aiccm2026dev_b_mp2	Run canonical closed-shell RI-MP2 on the B finite translation group.
vibeqc.run_aiccm2026dev_b_ccsd	Run complete-domain finite-torus restricted CCSD.
vibeqc.run_aiccm2026dev_b_ccsd_t	Run complete-domain finite-torus restricted CCSD(T).
vibeqc.run_aiccm2026dev_b_ump2	Run canonical finite-torus RI-UMP2 in the exact PNO limit.
vibeqc.run_aiccm2026dev_b_uccsd	Run full-domain finite-torus UCCSD with the O(N^6) oracle.
vibeqc.run_aiccm2026dev_b_uccsd_t	Run full-domain finite-torus UCCSD(T) with the O(N^6) oracle.
vibeqc.run_aiccm2026dev_b_dlpno_mp2	Run local-PNO MP2 on the exact real representation of the B torus.
vibeqc.run_aiccm2026dev_b_dlpno_ccsd	Run local-PNO CCSD on the real finite-torus B Hamiltonian.
vibeqc.run_aiccm2026dev_b_dlpno_ccsd_t	Run local-PNO CCSD(T) on the real finite-torus B Hamiltonian.
vibeqc.run_aiccm2026dev_b_dlpno_ump2	Run PBC-localized, pair-natural-orbital UMP2 on the B torus.
vibeqc.run_aiccm2026dev_b_dlpno_uccsd	Run the unrestricted local-PNO CCSD correctness pilot.
vibeqc.run_aiccm2026dev_b_dlpno_uccsd_t	Run the unrestricted local-PNO CCSD(T) correctness pilot.
vibeqc.derive_aiccm2026dev_b_scf_properties	Derive all currently supported gauge-invariant SCF properties.
vibeqc.aiccm2026dev_b_mayer_bond_orders	Return primitive-cell Mayer bond orders from a χ-CCM SCF result.
vibeqc.aiccm2026dev_b_band_structure	Sample the converged finite-torus Fock matrix along a k-path.
vibeqc.localize_aiccm2026dev_b_occupied	Localize the converged occupied space of an AICCM2026DEV-B SCF.
vibeqc.localize_aiccm2026dev_b_unrestricted_occupied	Localize the alpha and beta occupied projectors of a B-stream UHF.
vibeqc.AICCM2026DevBLocalizationResult	Localized occupied orbitals on the real BvK torus.
vibeqc.AICCM2026DevBLocalizationMethod	Available occupied-space gauges.
vibeqc.projected_atomic_orbitals	Project occupieds from selected AOs and canonically orthogonalize.
vibeqc.build_pair_natural_orbitals	Diagonalize the Hermitian MP2 model pair density.
vibeqc.enumerate_pair_orbits	Partition all unordered occupied pairs under supplied generators.
vibeqc.AICCM2026DevBLocalCorrelationSpace	Validated finite-torus PAO and occupied-pair bookkeeping.
vibeqc.build_aiccm2026dev_b_symmetry_plan	Analyze the space group and its exact action on a finite BvK torus.
vibeqc.shell_pair_orbits	Partition intrinsic-unique primitive shell pairs by point symmetry.
vibeqc.shell_quartet_orbits	Partition intrinsic 8-fold-unique primitive shell quartets.
vibeqc.AICCM2026DevBSymmetryPlan	Verified symmetry metadata for one finite cyclic cluster.
vibeqc.AICCM2026DevBBackend	Electron-repulsion backend for the same finite-torus functional.
vibeqc.AICCM2026DevBFiniteTorusConvention	Finite-N Hamiltonian convention attached to every B-stream result.
vibeqc.AICCM2026DevBMP2Result	Canonical finite-torus RI-MP2 energy per primitive cell.
vibeqc.AICCM2026DevBDLPNOMP2Result	Local-PNO MP2 result on the B finite torus, per primitive cell.
vibeqc.AICCM2026DevBDLPNOCCSDResult	Local-PNO CCSD or CCSD(T) result on the B finite torus.
vibeqc.cyclic_gamma_mesh	Return the reciprocal irreps of a finite cyclic cluster.
vibeqc.wigner_seitz_representatives	Construct the exact minimum-image partition of the cyclic group.
vibeqc.pair_wigner_seitz_representatives	Wigner--Seitz representatives for translations of centre B about A.
vibeqc.inverse_bloch_transform	Transform k-block matrices to primitive-translation blocks.
vibeqc.AICCM2026DevBDiagnostics	Internal-consistency data attached to an AICCM2026DEV_B result.
vibeqc.run_rhf_periodic_gamma_ewald2d	Gamma-point closed-shell periodic RHF with rigorous 2D slab Ewald.
vibeqc.run_rhf_periodic_gamma_ewald3d	Γ-point closed-shell periodic RHF SCF with Ewald-3D Coulomb.
vibeqc.run_rks_periodic_gamma_ewald3d	Γ-point closed-shell periodic Kohn-Sham SCF with Ewald-3D Coulomb.
vibeqc.run_uhf_periodic_gamma_ewald3d	Γ-point open-shell UHF SCF with the EWALD_3D Coulomb dispatch.
vibeqc.run_uks_periodic_gamma_ewald3d	Γ-point open-shell periodic Kohn-Sham SCF with Ewald-3D Coulomb.
vibeqc.run_rhf_periodic_multi_k_ewald3d	Multi-k closed-shell periodic RHF SCF with EWALD_3D Coulomb.
vibeqc.run_rks_periodic_multi_k_ewald3d	Multi-k closed-shell periodic RKS SCF with EWALD_3D Coulomb.
vibeqc.run_uhf_periodic_multi_k_ewald3d	Multi-k open-shell UHF SCF with EWALD_3D Coulomb.
vibeqc.run_pbc_bipole_rhf	Multi-k closed-shell RHF via the CRYSTAL-gauge BIPOLE scaffold.
vibeqc.run_pbc_bipole_uhf	Multi-k open-shell UHF via the CRYSTAL-gauge BIPOLE scaffold.
vibeqc.run_pbc_bipole_rks	Multi-k closed-shell RKS via the CRYSTAL-gauge BIPOLE scaffold.
vibeqc.run_pbc_bipole_uks	Multi-k open-shell UKS via the CRYSTAL-gauge BIPOLE scaffold.
vibeqc.run_periodic_job	Run a periodic SCF job and write the standard output files.
vibeqc.PeriodicRHFGDFResult	Result of run_rhf_periodic_gamma_gdf().
vibeqc.PeriodicRHFEwaldResult	Result of run_rhf_periodic_gamma_ewald3d().
vibeqc.PeriodicRHFMultiKEwaldResult	Result of run_rhf_periodic_multi_k_ewald3d().
vibeqc.PeriodicRKSEwaldResult	Result of run_rks_periodic_gamma_ewald3d().
vibeqc.PeriodicRKSMultiKEwaldResult	Result of run_rks_periodic_multi_k_ewald3d().
vibeqc.PeriodicUHFEwaldResult	Result of run_uhf_periodic_gamma_ewald3d().
vibeqc.PeriodicUHFMultiKEwaldResult	Result of run_uhf_periodic_multi_k_ewald3d().
vibeqc.PeriodicUKSEwaldResult	Result of run_uks_periodic_gamma_ewald3d().
vibeqc.PeriodicUKSMultiKEwaldResult	Result of run_uks_periodic_multi_k_ewald3d().
vibeqc.PeriodicKRHFGDFResult	Result of run_krhf_periodic_gdf().
vibeqc.PeriodicKRKSGDFResult	Result of run_krks_periodic_gdf().
vibeqc.PBCBipoleRHFResult	Result of run_pbc_bipole_rhf().
vibeqc.PBCBipoleUHFResult	Result of run_pbc_bipole_uhf().
vibeqc.PBCBipoleRKSResult	Result of run_pbc_bipole_rks().
vibeqc.PBCBipoleUKSResult	Result of run_pbc_bipole_uks().
vibeqc.PBCGDFResult	SCF result from run_pbc_gdf_rhf() / run_pbc_gdf_rks().

Periodic gradients + stress + properties

vibeqc.compute_gradient_periodic_rhf_gamma	Analytic Γ-only periodic RHF atomic gradient.
vibeqc.compute_gradient_periodic_rks_gamma	Analytic Γ-only periodic RKS atomic gradient (closed-shell DFT).
vibeqc.compute_stress_tensor	Force virial -- NOT the true periodic stress.
vibeqc.hirshfeld_charges	Classical Hirshfeld atomic partial charges from a converged SCF.
vibeqc.HirshfeldResult	Output of hirshfeld_charges().

ECPs + auto-population

vibeqc.ECPCenter
vibeqc.auto_ecp_centers	Build (ecp_centers, library_name) from a Molecule + basis name.
vibeqc.compute_ecp_matrix	Compute the AO-basis ECP matrix V_ECP_{muν} = <chi_mu|V_ECP|chi_ν> via libecpint's built-in XML library (ecp10mdf, ecp28mdf, ecp46mdf, ecp60mdf, ecp78mdf, lanl2dz).

QVF output

vibeqc.output.formats.qvf.write_qvf	Write {stem}.qvf.
vibeqc.output.formats.qvf.validate_qvf	Validate a QVF against the canonical SSOT schema.
vibeqc.output.formats.qvf.qvf_density_data	Evaluate total electron density on a uniform grid and return a dict suitable for write_qvf(..., volume_data=...).
vibeqc.output.formats.qvf.qvf_mo_data	Evaluate MO wavefunctions on a uniform grid and return a list suitable for write_qvf(..., mo_data=...).

Thermodynamics

vibeqc.ThermoResult

Output of compute_thermochemistry().

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[1]

Γ-CCM and χ-CCM are distinct CCM construction approaches: union-and-weight/Wigner-Seitz integral weighting and finite-translation-group characters, respectively. A declared common exchange-q=0 convention is a comparison constraint, not an identification of the constructions. Their distinction is not a choice of Coulomb kernels, and equality for a specified operator and route must be established rather than inferred from the labels.