{
  "abstract": "Understanding how collective ion transport emerges from equilibrium fluctuations is central to electrolyte statistical mechanics. Finite-volume fluctuations provide an accessible route to this information, but their interpretation is complicated because they mix wave numbers and collective fields. Here, we extend the finite-volume counting framework for inferring collective ion diffusion by combining the exact window projection with an inertial independent-particle reference, and apply it to a symmetric 1:1 solvent primitive model. The growth of ion-number fluctuations between the ballistic and plateau regimes appears nearly ideal, but this apparent ideality results from compensation between negative structural and positive dynamical excess contributions. The coupled ion-number--solvent relaxation further reveals a signed redistribution between solvent-associated and solvent-orthogonal projections that is largely hidden in the total response. The inferred collective diffusion depends on observation length and dynamical closure: measured structure alone does not systematically improve the estimate, whereas the coupled-field description reduces the high-concentration discrepancy. These results provide a basis for analyzing more realistic electrolytes with mutually coupled ion-number, charge, and solvent fluctuations.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.20503",
  "author_total": 1,
  "authors": [
    {
      "name": "Jeongmin Kim"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bxjxryf122d97.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.20503",
  "fulltext_url": null,
  "id": "bxjxryf122d97",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.20503",
  "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",
      "cond-mat.soft"
    ],
    [
      "arxiv",
      "physics.chem-ph"
    ],
    [
      "openalex",
      "1606|Electrostatics and Colloid Interactions"
    ]
  ],
  "openalex": "W7213611770",
  "pdf_url": "https://arxiv.org/pdf/2609.20503",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-17",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bxjxryf122d97.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:22:19Z",
      "native_id": "2609.20503",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.20503"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "arxiv:physics.chem-ph",
      "subfield": "physical"
    },
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.soft",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Collective Ion Dynamics from Finite-Volume Fluctuations in Model Explicit-Solvent Electrolytes",
  "title_text": "Collective Ion Dynamics from Finite-Volume Fluctuations in Model Explicit-Solvent Electrolytes",
  "type": "preprint",
  "updated_at": "2026-10-30T12:22:19Z",
  "url": "https://research.draconitic.com/paper/bxjxryf122d97",
  "venue": "arXiv",
  "versions": []
}