{
  "abstract": "Atomic benchmarks for sixth-period elements (Cs-Rn) are established to sub-millihartree precision under correlation-consistent effective core potentials (ccECPs) using coupled-cluster [up to CCSDT(Q)] and full configuration interaction methods. These references systematically characterize electron correlation, potential-to-kinetic energy partitioning, and combined fixed-node and locality biases ($η$) in fixed-node diffusion Monte Carlo (FNDMC). The valence kinetic-to-total energy ratio ($ξ$) departs from the non-relativistic all-electron Coulombic virial limit ($ξ=100\\%$), remaining confined between 25.8$\\%$ and 37.6$\\%$. The Un-pseudizing of semi-core shells decreases $ξ$ as the attractive potential energy deepens faster than the accompanying kinetic energy escalates. Periodic trends in $ξ$ reveal a $5d$ plateau near 34$\\%$, with a lanthanide-contraction-driven maximum in Hf, followed by a sharp decline across the $6p$ block. In FNDMC, $η$ escalates rapidly at the onset of group-1/2 and toward the $6p$ closed-shell limit, peaking at 5.42$\\%$ in Rn. Although fixed-node errors dominate $η$ in most sixth-period elements, a locality error inversion occurs in Bi, with Pb exhibiting comparable error magnitudes. Furthermore, core-valence partitioning alters trial wavefunction nodal topology: in Tl, three-dimensional nodal cross-sections reveal isolated toroidal domains that confine walkers. This work completes the periodic-table-wide ccECP database from H to Rn, revealing how pseudopotential choices govern energy partitioning, nodal topology, and the balance between fixed-node and localization errors.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.24450",
  "author_total": 2,
  "authors": [
    {
      "name": "Omar Madany"
    },
    {
      "name": "Lubos Mitas"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/dr6dr8w3cjs0c.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.24450",
  "fulltext_url": null,
  "id": "dr6dr8w3cjs0c",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.24450",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "arxiv",
      "cond-mat.str-el"
    ],
    [
      "arxiv",
      "physics.chem-ph"
    ],
    [
      "openalex",
      "3107|Advanced Chemical Physics Studies"
    ]
  ],
  "openalex": "W7223060140",
  "pdf_url": "https://arxiv.org/pdf/2610.24450",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-17",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/dr6dr8w3cjs0c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:30:52Z",
      "native_id": "2610.24450",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.24450"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Accurate Atomic Correlation Energies and Virial Trends for Correlation-Consistent Effective Core Potentials III: Quantitative Separation of Fixed-Node Biases and Localization Errors in Cs-Rn",
  "title_text": "Accurate Atomic Correlation Energies and Virial Trends for Correlation-Consistent Effective Core Potentials III: Quantitative Separation of Fixed-Node Biases and Localization Errors in Cs-Rn",
  "type": "preprint",
  "updated_at": "2026-10-30T12:33:41Z",
  "url": "https://research.draconitic.com/paper/dr6dr8w3cjs0c",
  "venue": "arXiv",
  "versions": []
}