atomref-proatoms

atomref-proatoms is a reproducible data package for spherical neutral proatomic radial electron densities. It publishes named profile datasets, cutoff radii, and QA tables generated from declared atomic states, frozen basis files, mean-field settings, radial grids, and validation criteria.

The package addresses a common ambiguity in proatom data. Open-shell atoms are not generally spherical in an ordinary determinant calculation: the SCF procedure can occupy particular magnetic components and optimize an anisotropic density. Post-SCF angular averaging converts that density into a radial curve, but it does not make the underlying self-consistent reference spherical. Here the spherical constraint is imposed inside the atomic SCF model through fractional occupations and angular-momentum block averaging. The tabulated density is therefore the self-consistent spherical proatom density intended by the dataset definition.

The current v1 datasets are neutral-only:

• pbe0_sfx2c_x2cqzvpall_h-rn_spherical_v1, covering H-Rn with x2c-QZVPall.
• pbe0_sfx2c_dyallv4z_h-lr_spherical_v1, covering H-Lr with dyall-v4z.

Both use unrestricted PBE0 with PySCF 2.13.1, spin-free one-electron X2C, and pure/spherical Gaussian basis functions.

Documentation sections

• Scientific model explains the density definition, spherical SCF construction, radial grids, cutoff radii, and QA model.
• Data products describes the released profile, radii, and QA files.
• Input data describes the basis-set bundles and atomic-state table.
• Workflow documents the scripts and regeneration commands.
• Notebooks collect practical reports and method demos.
• License and AI assistance note record repository attribution and responsibility statements.

Minimal validation

python scripts/check_basis_bundles.py
python scripts/build_atom_states.py --check
pytest

The generator itself is optional for users who only need released data tables. SCF regeneration requires the generator dependency extra.