{
  "abstract": "Time-derivative couplings (TDCs) are central ingredients in mixed quantum-classical simulations of nonadiabatic dynamics, yet their evaluation remains a key practical challenge when analytic nonadiabatic coupling vectors or wave function overlaps are unavailable. Curvature-driven approximations provide an appealing alternative by evaluating TDCs from adiabatic potential energies or gradients along nuclear trajectories, motivated by the one-dimensional Baeck-An model. In this work, we examine curvature-based TDC approximations within trajectory surface hopping (TSH) and coherent switching with decay of mixing (CSDM), and introduce a modified gradient-based curvature-only formulation that retains the directional-curvature contribution to the TDC while omitting the explicit acceleration-dependent term at all times in the coupling evaluation. The performance of energy-based, gradient-based, and curvature-only TDCs is evaluated for four benchmark systems of increasing dynamical complexity: ethylene, DMABN, fulvene, and SO2. For ethylene, all curvature-driven schemes closely reproduce reference dynamics obtained with analytic nonadiabatic couplings. For DMABN and fulvene, which involve repeated nonadiabatic passages and back-transfer, the curvature-only approximation yields improved agreement with reference populations by reducing overpopulation effects observed with standard curvature formulations. In the multistate singlet-triplet dynamics of SO2, standard curvature-based TDCs introduce spurious population transfer to the ground state, an artifact that is significantly decreased by the curvature-only scheme in both TSH and CSDM. Overall, the results show that removing the acceleration-dependent contribution leads to a more robust curvature-driven TDC approximation across a wide range of nonadiabatic regimes, while retaining the conceptual simplicity and efficiency of curvature-based approximations.",
  "abstract_shown": true,
  "affiliations": [
    "Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Straße 17, 1090Vienna, Austria."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 2,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Feven-Alemu Korsaye"
    },
    {
      "affs": [
        0
      ],
      "name": "Leticia González",
      "orcid": "0000-0001-5112-794X"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/6w96hjs6pp7qg.bib",
  "cited_by": 0,
  "doi": "10.1021/acs.jctc.6c01219",
  "fulltext_url": "https://europepmc.org/articles/PMC13602848",
  "id": "6w96hjs6pp7qg",
  "issns": [
    "1549-9618",
    "1549-9626"
  ],
  "landing_url": "https://europepmc.org/article/MED/42917482",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Spectroscopy and Quantum Chemical Studies"
    ]
  ],
  "openalex": "W7212171968",
  "pdf_url": "https://europepmc.org/articles/PMC13602848?pdf=render",
  "pmcid": "PMC13602848",
  "pmid": "42917482",
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/6w96hjs6pp7qg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:02Z",
      "native_id": "MED:42917482",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42917482"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Spectroscopy and Quantum Chemical Studies",
      "subfield": "amo"
    }
  ],
  "title": "Gradient-Based Curvature-Only Time-Derivative Coupling for Surface Hopping and Coherent Switching with Decay of Mixing: Application to SO2 and Molecular Tully Models.",
  "title_text": "Gradient-Based Curvature-Only Time-Derivative Coupling for Surface Hopping and Coherent Switching with Decay of Mixing: Application to SO2 and Molecular Tully Models.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:21:02Z",
  "url": "https://research.draconitic.com/paper/6w96hjs6pp7qg",
  "venue": "Journal of chemical theory and computation",
  "versions": []
}