{
  "model": "Hchain",
  "lattice": "chain",
  "n_sites": 10,
  "boundary": "O",
  "params": {
    "N_up": 5,
    "N_dn": 5,
    "R": 1.2,
    "basis": "cc-pVQZ"
  },
  "instance_id": "Hchain/chain_10_O_R1.2_ccpvqz",
  "rows": [
    {
      "energy": -5.1419,
      "sigma": 0.0008,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "ph-AFQMC",
      "ansatz": null,
      "method_detail": "",
      "method_as_published": "AFQMC [phaseless]",
      "family": "AFQMC / GFMC",
      "bound_type": "projected",
      "bound_type_reason": "AFQMC, fixed-node or lattice-regularised DMC, coupled cluster, MRCI+Q or an embedding method; not a bound (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-5.1419   0.0008 (total for N = 10; second number the stated uncertainty)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/AFQMC_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX commit b99a183 (data committed in d54c7fa, 2017-10-09, by the first author): raw file fetched from raw.githubusercontent.com at b99a183 and byte-compared with sources/1705.01608-data-b99a183.tsv (scripts/fetch_raw.mjs, raw-compare2.json); paper read for conventions (PRX 7, 031059 (2017), journal text sources/1705.01608-PhysRevX.7.031059.txt (published 2017-09-28, corrected 2021-03-24); arXiv:1705.01608v2 (dated 2017-11-08), sources/1705.01608.txt)",
          "location": "dataset file N_10_OBC/R_1.2/AFQMC_basis-QZ (no finite-N AFQMC value for this N/basis/trial is printed in the paper, whose finite-N tables cover H10 in STO-6G and CBS only)",
          "reported_as": "-5.1419   0.0008 (file content: total energy in Hartree with nuclear repulsion, then its 1-sigma statistical error)",
          "conversion": "total stored as is (-5.1419); eps = -5.1419/10 = -0.5141900000; sigma 0.0008/10 = 8.000000e-05 per atom",
          "note": "open chain N = 10, R = 1.2 bohr, N_up = N_dn = 5, basis cc-pVQZ (README: QZ = cc-pVQZ); projected (phaseless AFQMC, UHF trial), own computation. peer_reviewed: the data were committed 11 days after publication (see report).",
          "secondary_of": null,
          "source_entry": "h-motta17-afqmc-c1#13 (qmbl-verify 2026-10-23/24, verified)"
        }
      }
    },
    {
      "energy": -5.140214,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "RCCSD(T)",
      "ansatz": null,
      "method_detail": "",
      "method_as_published": "RCCSD(T)",
      "family": "FCIQMC / CC",
      "bound_type": "approximate",
      "bound_type_reason": "finite-order perturbation theory, GW, or a perturbative correction to coupled cluster (track 3, 2026-10-21); error of unknown sign (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-5.140214 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RCCSD(T)_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX at b99a183a5a2dd2a471bbde3f3c4952cc3d2432ea (2017-10-09, authors' upload, CC BY 4.0): raw file fetched fresh from raw.githubusercontent.com on 2026-10-24 (sources/1705.01608-data-raw-rccsd-t.json, out/h-motta17-rccsd-t--c1/fetch_raw.mjs) and compared byte-for-byte with the committed TSV qmbl-wt-hydrogen/sources/1705.01608-data-b99a183.tsv (compare.py); conventions from journal Phys. Rev. X 7, 031059 (2017; published 2017-09-28, corrected 2021-03-24), publisher PDF text qmbl-wt-hydrogen/sources/1705.01608-PhysRevX.7.031059.txt; arXiv:1705.01608v2 (dated 2017-11-08, PDF stamp 'arXiv:1705.01608v2'), sources/1705.01608.txt; table cells parsed with python (out/h-motta17-rccsd-t--c1/compare.py)",
          "location": "dataset file N_10_OBC/R_1.2/RCCSD(T)_basis-QZ (the paper prints no finite-basis RCCSD(T) value for this N and basis: Table II is STO-6G H10, Table III CBS H10, Table IV MRCI+Q only, Tables V-VI thermodynamic limit)",
          "reported_as": "-5.140214 (Hartree, total for N = 10, nuclear repulsion included)",
          "conversion": "total as printed; per atom -5.140214 / 10 = -0.514021400 = stored eps -0.5140214000000001",
          "note": "RCCSD(T) on an RHF reference (Sec. III, journal lines 226-229; App. A 1, PySCF, journal lines 806-820); open equispaced chain, R in bohr, neutral, N_up = N_dn = N/2 (lowest-energy RHF determinant); bound_type approximate per RULES §13.4 (CCSD(T), provisional 2026-10-21); no sigma for a finite-basis deterministic energy; the UCCSD(T) row of the same paper on this instance (pass 128, '-5.140214 (total for N = 10)') carries the identical number: at these R the UHF solution collapses to RHF (paper Sec. IV C: 'using UHF as a reference gives numerically indistinguishable results, except for very short bond lengths and large sizes'), so the two cells are one calculation; same batch, not a duplicate-row from another batch",
          "secondary_of": null,
          "source_entry": "h-motta17-rccsd-t--c1#8 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-5.140214 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RCCSD(T)_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    },
    {
      "energy": -5.134665,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "RCCSD",
      "ansatz": null,
      "method_detail": "",
      "method_as_published": "RCCSD",
      "family": "FCIQMC / CC",
      "bound_type": "projected",
      "bound_type_reason": "AFQMC, fixed-node or lattice-regularised DMC, coupled cluster, MRCI+Q or an embedding method; not a bound (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-5.134665 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RCCSD_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "journal PRX 7, 031059 (2017) publisher PDF, pypdf layout extraction (raw/journal-layout.txt), cross-read with the project text sources/1705.01608-PhysRevX.7.031059.txt; arXiv:1705.01608v2 PDF (dated November 8, 2017), pypdf layout (raw/arxiv-layout.txt) and sources/1705.01608.txt; data repository github.com/simonsfoundation/hydrogen-benchmark-PRX at b99a183, files fetched raw from GitHub 2026-10-24 (raw/rccsd-files-b99a183.json) and compared with sources/1705.01608-data-b99a183.tsv by check.mjs",
          "location": "dataset file N_10_OBC/R_1.2/RCCSD_basis-QZ (github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183, 2017-10-09, uploaded by the authors); raw GitHub content '-5.134665' equals the committed TSV line",
          "reported_as": "-5.134665 (file content, total for N = 10, Hartree)",
          "conversion": "stored eps -0.5134665 x 10 = -5.134665 = file value; -5.134665 / 10 = -0.51346650 per atom",
          "note": "Instance agrees: equally spaced H10 chain, open (finite molecule), R = 1.2 bohr, dataset basis label QZ = cc-pVQZ (README basis list), N_up = N_dn = 5. Number first printed in the dataset, cited to it with the paper as method reference (RULES 8); the paper prints no finite-basis RCCSD table for N = 10 beyond STO-6G. bound_type projected (RULES 13.4), sampled false, sigma null (file holds one number) agree. Same-instance dataset values: AFQMC -5.1419; the row is above every DMRG/AFQMC/MRCI+Q value on the instance. Computed with near-linear-dependent basis vectors removed at overlap threshold 1e-7 (App. A a: affects cc-pVTZ/QZ at R < 1.6 and cc-pVDZ at R < 1.4; the authors give ~1e-6 Ha per atom as the size of threshold effects): noted, not a different instance. Duplicate scan: no data/Hchain file exists (track 3 held); no row from another batch on this instance carries this number. The 1705.01608 UCCSD row (pass 133) prints the same number because the UHF solution collapses to RHF at this geometry; a separate dataset file and column, a different method label, not a duplicate-row.",
          "secondary_of": null,
          "source_entry": "h-motta17-rccsd-c1#8 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-5.134665 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RCCSD_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    },
    {
      "energy": -4.88271313171,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "HF",
      "ansatz": null,
      "method_detail": "restricted",
      "method_as_published": "RHF",
      "family": "mean field",
      "bound_type": "variational",
      "bound_type_reason": "the energy of a stated wave function (Hartree-Fock, DMRG at a stated bond dimension, MRCI, VMC, a neural-network state); an upper bound in the instance's basis (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-4.882713131707 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RHF_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX b99a183, raw file fetched from raw.githubusercontent.com (raw-rhf-b99a183.json), compared with the committed TSV and the stored row by compare.mjs",
          "location": "dataset file N_10_OBC/R_1.2/RHF_basis-QZ (number first printed in the dataset; Table II prints RHF only for H10 STO-6G; journal Appendix B: 'Data not included in the appendixes are available online [11]', Ref. [11] = this repository)",
          "reported_as": "-4.882713131707 (total Hartree for N = 10)",
          "conversion": "total as printed; per atom -4.882713131707/10 = -0.4882713131707 (stored eps identical to 1e-12); no uncertainty in the file, sigma null",
          "note": "Instance chain N = 10, open (folder N_10_OBC), R = 1.2 bohr (folder R_1.2), basis cc-pVQZ (README basis list 'QZ :   cc-pVQZ'), N_up = N_dn = 5. RHF variational (RULES 13.4), deterministic. Raw file equals the committed TSV. No same-number row from another batch on this instance. Appendix A 1 a (journal txt ~lines 769-778): for cc-pVTZ/QZ/5Z at R < 1.6 and cc-pVDZ at R < 1.4 'We remove linearly dependent vectors with an overlap threshold of 10^-7' and a smaller threshold 'in the Hartree-Fock calculation' would change the energy 'by ~10^-6 EHa per atom'; the energy is then RHF in the thresholded (sub)space of cc-pVQZ, still an upper bound for the instance.",
          "secondary_of": null,
          "source_entry": "h-motta17-rhf-c1#9 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-4.882713131707 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/RHF_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    },
    {
      "energy": -5.140214,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "UCCSD(T)",
      "ansatz": null,
      "method_detail": "",
      "method_as_published": "UCCSD(T)",
      "family": "FCIQMC / CC",
      "bound_type": "approximate",
      "bound_type_reason": "finite-order perturbation theory, GW, or a perturbative correction to coupled cluster (track 3, 2026-10-21); error of unknown sign (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-5.140214 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UCCSD(T)_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "data repository github.com/simonsfoundation/hydrogen-benchmark-PRX at b99a183a5a2dd2a471bbde3f3c4952cc3d2432ea (2017-10-09, repository HEAD on 2026-10-24, README: CC BY 4.0); all 90 UCCSD(T)_* files fetched raw from GitHub (sources/1705.01608-data-raw-uccsd-t.json, out/h-motta17-uccsd-t-/fetch_raw.mjs), byte-equal to the committed TSV qmbl-wt-hydrogen/sources/1705.01608-data-b99a183.tsv; comparison by out/h-motta17-uccsd-t-/check.py; conventions from journal Phys. Rev. X 7, 031059 (2017; published 2017-09-28, corrected 2021-03-24), publisher PDF text qmbl-wt-hydrogen/sources/1705.01608-PhysRevX.7.031059.txt; arXiv:1705.01608v2 (dated November 8, 2017), qmbl-wt-hydrogen/sources/1705.01608.txt",
          "location": "dataset file N_10_OBC/R_1.2/UCCSD(T)_basis-QZ (the paper prints no UCCSD(T) value for N = 10 in basis cc-pVQZ: Table II is STO-6G H10, Table III CBS H10, Table IV MRCI+Q only, Tables V-VI the thermodynamic limit)",
          "reported_as": "-5.140214 (Hartree, total for N = 10, nuclear repulsion included)",
          "conversion": "total as printed; per atom -5.140214 / 10 = -0.514021400 = stored eps -0.5140214000000001",
          "note": "UCCSD(T) = CCSD with perturbative triples on a UHF reference (journal Sec. III lines 234-237: 'using UHF as a reference state'; dataset README: 'unrestricted coupled-cluster ... perturbative treatment of triples'); PySCF (App. A a); open equispaced chain, N = 10, R = 1.2 bohr, neutral, N_up = N_dn = N/2 (Sec. II), basis cc-pVQZ; total energy in Hartree with nuclear repulsion (C1/C2 card); bound_type approximate per RULES 13.4 (CCSD(T) provisional 2026-10-21); deterministic, no sigma; no duplicate in qmbl-wt-hydrogen/data/ (no Hchain model there: track 3 not loaded); identical to the RCCSD(T) row of the same paper on this instance (dataset UHF = RHF within 0.003 mHa here, so the two are one calculation; same batch, the paper/dataset prints both methods, not a duplicate-row)",
          "secondary_of": null,
          "source_entry": "h-motta17-uccsd-t-#8 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-5.140214 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UCCSD(T)_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    },
    {
      "energy": -5.134665,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "UCCSD",
      "ansatz": null,
      "method_detail": "",
      "method_as_published": "UCCSD",
      "family": "FCIQMC / CC",
      "bound_type": "projected",
      "bound_type_reason": "AFQMC, fixed-node or lattice-regularised DMC, coupled cluster, MRCI+Q or an embedding method; not a bound (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-5.134665 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UCCSD_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "journal PDF PRX 7, 031059 (2017) (sources/1705.01608-PhysRevX.7.031059.pdf) and arXiv:1705.01608v2 PDF (dated November 8, 2017), both extracted with pypdf layout mode (out/h-motta17-uccsd-c1/raw/*-layout.txt); data repository github.com/simonsfoundation/hydrogen-benchmark-PRX at b99a183, every UCCSD_* file fetched raw from GitHub on 2026-10-24 (raw/uccsd-files-b99a183.json), byte-equal to the committed TSV",
          "location": "data repository file N_10_OBC/R_1.2/UCCSD_basis-QZ (the paper prints no finite-basis UCCSD value for N = 10 in cc-pVQZ: Table II is STO-6G H10, Table III CBS H10, Table IV MRCI+Q only, Tables V-VI thermodynamic limit)",
          "reported_as": "-5.134665 (total, Hartree)",
          "conversion": "stored per atom -0.5134665 x 10 = -5.134665; equals the file value",
          "note": "identical to the RCCSD value of the same paper on this instance (UHF collapses to RHF here, dataset UHF = RHF); not a duplicate-row: the paper prints both methods; near-linearly-dependent basis functions removed at overlap threshold 1e-7 (App. A a: 'cc-pVTZ, cc-pVQZ, and cc-pV5Z at geometries R < 1.6 aB and cc-pVDZ at R < 1.4 aB'); the paper puts the effect at ~1e-6 Ha per atom; N_up = N_dn = N/2, OBC, R in bohr, total with nuclear repulsion, bound_type and peer_reviewed agree; no data/Hchain file exists (track 3 held); no row from another batch on this instance carries this number",
          "secondary_of": null,
          "source_entry": "h-motta17-uccsd-c1#9 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-5.134665 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UCCSD_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    },
    {
      "energy": -4.88271020551,
      "sigma": null,
      "energy_variance": null,
      "dof": 10,
      "einf": null,
      "v_score": null,
      "method": "HF",
      "ansatz": null,
      "method_detail": "unrestricted",
      "method_as_published": "UHF",
      "family": "mean field",
      "bound_type": "variational",
      "bound_type_reason": "the energy of a stated wave function (Hartree-Fock, DMRG at a stated bond dimension, MRCI, VMC, a neural-network state); an upper bound in the instance's basis (RULES.md 13.4; assigned during source reading)",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "peer_reviewed": true,
      "source": "track3-2026-10-20",
      "provenance": "primary",
      "verified": {
        "checked_on": "2026-10-20",
        "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0; source text of arXiv:1705.01608 read locally (pypdf layout text; the generator finds every value again on its line), no LLM transcription of numbers; single reading",
        "reported_as": "-4.882710205505 (total for N = 10)",
        "note": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UHF_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference | Hartree, lengths in bohr (Appendix B). Total energies with nuclear repulsion: FCI/STO-6G H10 at R = 1.8 is -5.42438538 in the dataset and -0.542439 per atom in Table II, and the paper's FCI E_inf = -0.471039 is the STO-6G hydrogen-atom energy per atom.",
        "secondary_of": null,
        "second_read": {
          "checked_on": "2026-10-24",
          "scope": "value",
          "method": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX b99a183, raw UHF file fetched from raw.githubusercontent.com (raw-uhf-b99a183.json), compared with the committed TSV, the stored row, the journal text (PRX 7, 031059) and arXiv:1705.01608v2 text by compare.mjs; QMBL pyscf FCI/RHF for STO-6G",
          "location": "dataset file N_10_OBC/R_1.2/UHF_basis-QZ (number first printed in the dataset; the journal cites the repository as Ref. [11], Appendix B 'Data not included in the appendixes are available online [11]')",
          "reported_as": "-4.882710205505 (total Hartree for N = 10)",
          "conversion": "total as printed; per atom -4.882710205505/10 = -0.48827102055 (stored eps identical to 1e-12); no uncertainty in the file, sigma null",
          "note": "Instance chain, N = 10, open (dataset folder N_10_OBC), R = 1.2 bohr, basis cc-pVQZ, N_up = N_dn = 5. UHF = unrestricted Hartree-Fock (journal method list, Ref. [51] Pople-Nesbet): variational (RULES 13.4), deterministic, method_detail empty, peer_reviewed true. Raw file equals the committed TSV; UHF decreases monotonically DZ > TZ > QZ > 5Z (order_check.mjs). Dataset UHF minus RHF on the same file set: +0.000002926 Ha (UHF a few 1e-6 or less above RHF: convergence/linear-dependence noise of the size the journal states, '~10^-6 EHa per atom', Appendix A 1 a; not a finding). No duplicate from another batch: the only same-number row on the instance is the same paper's RHF row (UHF converged to the restricted solution), a different method of the same batch; no data/Hchain file exists (track 3 held).",
          "secondary_of": null,
          "source_entry": "h-motta17-uhf-c1#11 (qmbl-verify 2026-10-23/24, verified)"
        }
      },
      "sampled": false,
      "corrections": [
        {
          "field": "sampled",
          "to": false,
          "reported_as": "-4.882710205505 (total for N = 10)",
          "location": "dataset github.com/simonsfoundation/hydrogen-benchmark-PRX, commit b99a183 (2017-10-09, uploaded by the authors), CC BY 4.0, file N_10_OBC/R_1.2/UHF_basis-QZ in sources/1705.01608-data-b99a183.tsv; number first printed in the dataset (RULES.md §8), the paper is the method reference",
          "checked_on": "2026-10-20",
          "reason": "Deterministic, not a Monte Carlo estimate, as the track-3 reader recorded it (pass row `sampled`); the method string alone reads the other way (units.mjs, isSampled).",
          "source_entry": "passes/track3/sweep-rows-2026-10-20-hydrogen.json"
        }
      ]
    }
  ],
  "url": "https://qmbl.org/i/Hchain/chain_10_O_R1.2_ccpvqz/",
  "per_site_divisor": 10,
  "per_site_label": "E/N (Ha)",
  "best": {
    "exact": null,
    "variational": {
      "energy": -4.88271313171,
      "sigma": null,
      "method": "HF",
      "ansatz": null,
      "method_detail": "restricted",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "bound_type": "variational",
      "energy_per_site": -0.48827131317100003
    },
    "projected": {
      "energy": -5.1419,
      "sigma": 0.0008,
      "method": "ph-AFQMC",
      "ansatz": null,
      "method_detail": "",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "bound_type": "projected",
      "energy_per_site": -0.5141899999999999
    },
    "extrapolated": null,
    "approximate": {
      "energy": -5.140214,
      "sigma": null,
      "method": "RCCSD(T)",
      "ansatz": null,
      "method_detail": "",
      "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
      "bound_type": "approximate",
      "energy_per_site": -0.5140214000000001
    },
    "below_exact": []
  },
  "no_best_reason": null,
  "record": {
    "energy": -5.1419,
    "sigma": 0.0008,
    "method": "ph-AFQMC",
    "ansatz": null,
    "method_detail": "",
    "reference": "M. Motta, D. M. Ceperley, G. K.-L. Chan, J. A. Gomez, E. Gull, S. Guo, C. A. Jiménez-Hoyos, T. N. Lan, J. Li, F. Ma, A. J. Millis, N. V. Prokof’ev, U. Ray, G. E. Scuseria, S. Sorella, E. M. Stoudenmire, Q. Sun, I. S. Tupitsyn, S. R. White, D. Zgid & S. Zhang, Towards the Solution of the Many-Electron Problem in Real Materials: Equation of State of the Hydrogen Chain with State-of-the-Art Many-Body Methods, Phys. Rev. X 7, 031059 (2017), arXiv:1705.01608, doi:10.1103/PhysRevX.7.031059",
    "bound_type": "projected",
    "energy_per_site": -0.5141899999999999
  },
  "no_record_reason": null
}
