oqp.export.fcidump

FCIDUMP export for OQP reference orbitals.

This delegates to the in-tree :mod:`oqp.quantum` package, which builds the
second-quantized Hamiltonian from OpenQP's *own* AO integrals (``OQP::Hcore``
and the native two-electron integrals ``OQP::ERI_AO``) in OpenQP's MO basis --
so the AO ordering/normalization is guaranteed consistent and the file is the
genuine OpenQP Hamiltonian (no foreign integral engine, nothing silently
mixed). It does not reimplement the writer.

:func:`verify_fcidump_fci` is an optional cross-check: read the FCIDUMP, run a
PySCF FCI, and compare to PySCF's native FCI for the same system (FCI is
invariant to the orbital choice, so this is a clean ground truth). It honours
the spin sector (``MS2``) recorded in the file, so open-shell dumps verify
correctly.

Functions

dump_fcidump(path, mol[, tol])
build_pyscf_mol(mol)
verify_fcidump_fci(path, mol)

Module Contents

dump_fcidump(path, mol, tol=1e-12)

Write a FCIDUMP for the OQP reference MOs via :mod:`oqp.quantum`.

Returns a small metadata dict (norb / nelec / ms2 / core energy).

build_pyscf_mol(mol)

Construct a PySCF Mole matching the OQP molecule/basis (for the FCI
cross-check only).

verify_fcidump_fci(path, mol)

Read FCIDUMP -> PySCF FCI, honouring MS2; compare to native PySCF FCI.