{
  "annotation_id": "c62793f8-4f9c-4830-a3fa-3bd729c527bf",
  "date_created": "2026-02-17T05:53:16.177000Z",
  "date_modified": "2026-02-17T05:53:16.177000Z",
  "file_hash": "a7429ba3ade5718f2807fb76b3038618d2f2e1e05d9a4a97c08857bae6adcab8",
  "private": false,
  "record": {
    "abstract": "Ion transport underlies the operation of biological ion channels and governs the performance of electrochemical energy-storage devices. A long-standing anomaly is that smaller alkali metal ions, such as Li$^+$, migrate more slowly in water than larger ions, in apparent violation of the Stokes-Einstein relation. This breakdown is conventionally attributed to dielectric friction, a collective drag force arising from electrostatic interactions between a drifting ion and its surrounding solvent. Here, combining nanopore transport measurements over electric fields spanning several orders of magnitude with molecular dynamics simulations, we show that the time-averaged electrostatic force on a migrating ion is not a drag force but a net driving force. By contrasting charged ions with neutral particles, we reveal that ionic charge introduces additional Lorentzian peaks in the frequency-dependent friction coefficient. These peaks originate predominantly from short-range Lennard-Jones (LJ) interactions within the first hydration layer and represent additional channels for energy dissipation, strongest for Li$^+$ and progressively weaker for Na$^+$ and K$^+$. Our results demonstrate that electrostatic interactions primarily act to tighten the local hydration structure, thereby amplifying short-range LJ interactions rather than directly opposing ion motion. This microscopic mechanism provides a unified physical explanation for the breakdown of the Stokes-Einstein relation in aqueous ion transport.",
    "arxiv_id": "2601.08309",
    "authors": [
      "Zhenyu Wei",
      "Mu Chen",
      "Jun Ren",
      "Pinyao He",
      "Wei Xu",
      "Wei Liu",
      "Fei Zheng",
      "Yin Zhang",
      "Wei Si",
      "Jinjie Sha",
      "Zhonghua Ni",
      "Yunfei Chen"
    ],
    "categories": [
      "cond-mat.soft",
      "physics.chem-ph"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "title": "A microscopic origin for the breakdown of the Stokes Einstein relation in ion transport",
    "url": "https://arxiv.org/abs/2601.08309",
    "version": "v1"
  },
  "schema_id": "dorsal/arxiv",
  "source": {
    "execution_id": "03630c0d-f065-4385-bfe3-cae440d777f0",
    "id": "arXiv Dataset",
    "type": "Model",
    "variant": "snapshot-2026-01-17",
    "version": "0.1.0"
  },
  "user_id": 1000002
}