{
  "abstract": "Excited electronic states are difficult to accurately and tractably model, particularly those exhibiting multiexcitonic character. Scalable single-reference excited state methods typically fail to describe such states as they suffer from the defects of the mean-field approximation and/or neglect higher-rank excitation operators. To address this, we derive the [T] perturbative correction to the quantum self-consistent equation-of-motion unitary coupled cluster singles and doubles (q-sc-EOM-UCCSD) method. The method captures triple excitation effects through a classical step of second-order in many-body perturbation theory following a q-sc-EOM-UCCSD calculation on a quantum computer. The perturbative correction developed has a $\\mathcal{O}(N^7)$ classical computational time scaling. We incorporate [T] into a hybrid compute strategy wherein eigenvectors of the effective Hamiltonian from the hybrid quantum-classical q-sc-EOM-UCCSD algorithm are relayed to a classical computer which performs the postprocessing required for the [T] correction. The benefits of [T] are quantified in a benchmark covering a variety of electronically excited states of the isoelectronic CH$^+$ and BH molecules. We find that the addition of the [T] correction to both trotterized and full operator variants of q-sc-EOM-CCSD can offer dramatic improvements over baseline q-sc-EOM-UCCSD. Our assessment clearly demonstrates the importance of considering higher-rank excitation operators in q-sc-EOM-UCCSD, quantifies the overall success of the [T] correction, and discusses some of its limitations.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.09260",
  "author_total": 6,
  "authors": [
    {
      "name": "Zachary W. Windom"
    },
    {
      "name": "Prince Kwao"
    },
    {
      "name": "Luke Bertels"
    },
    {
      "name": "Daniel Claudino"
    },
    {
      "name": "Ayush Asthana"
    },
    {
      "name": "Rodney J. Bartlett"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/ak48e66mnpj3j.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.09260",
  "fulltext_url": null,
  "id": "ak48e66mnpj3j",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.09260",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.chem-ph"
    ],
    [
      "openalex",
      "3107|Advanced Chemical Physics Studies"
    ]
  ],
  "openalex": "W7221014496",
  "pdf_url": "https://arxiv.org/pdf/2610.09260",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-07",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/ak48e66mnpj3j.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:37Z",
      "native_id": "2610.09260",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.09260"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    }
  ],
  "title": "Resolving molecular biexcited states using classical leading-order triples corrections to quantum equation-of-motion UCCSD",
  "title_text": "Resolving molecular biexcited states using classical leading-order triples corrections to quantum equation-of-motion UCCSD",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:37Z",
  "url": "https://research.draconitic.com/paper/ak48e66mnpj3j",
  "venue": "arXiv",
  "versions": []
}