{
  "abstract": "We investigate the effect of static electric fields on the photoisomerisation dynamics of the penta-2,4-dieniminium cation (PSB3), a minimal model of the retinal chromophore of rhodopsins. The two-state, three-mode diabatic model of Marsili et al. is reparametrised against Rotated Multi-State Complete Active-Space Perturbation Theory at 2nd order (RMS-CASPT2) data that include the conical intersection, extended with hydrogen out-of-plane (HOOP) and higher torsional coupling terms, and complemented with torsion-dependent diabatic dipole moments fitted to finite-field RMS-CASPT2 energies. The new model reproduces the position and the sloped, single-path topography of the RMS-CASPT2 intersection. We show that the diabatic coupling must have the same parity as the transition dipole under reflection through the molecular plane, since otherwise an in-plane field artificially favours one sense of torsion.\n\nField-free quantum dynamics show that the conical intersection of the new model is more efficient. More population decays to the ground state when the wavepacket first reaches the twisted geometry and less remains trapped on the excited state, because",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "name": "Isabel Eder"
    },
    {
      "name": "Nicolas Ferré"
    },
    {
      "name": "Miquel Huix-Rotllant"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/0khc8586b9w9c.bib",
  "cited_by": 0,
  "doi": null,
  "fulltext_url": null,
  "id": "0khc8586b9w9c",
  "issns": [],
  "landing_url": "https://hal.science/hal-05801912v1",
  "language": "en",
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.chim"
    ],
    [
      "hal",
      "1.chim.theo"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://hal.science/hal-05801912/document",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/0khc8586b9w9c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:58Z",
      "native_id": "hal-05801912",
      "source": "hal",
      "url": "https://hal.science/hal-05801912v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "hal:1.chim.theo",
      "subfield": "theoretical"
    }
  ],
  "title": "Static Electric Field Effects on the Photoisomerisation of a Protonated Schiff Base Model",
  "title_text": "Static Electric Field Effects on the Photoisomerisation of a Protonated Schiff Base Model",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:58Z",
  "url": "https://research.draconitic.com/paper/0khc8586b9w9c",
  "venue": "HAL",
  "versions": []
}