{
  "abstract": "Shared protons in dicarboxylate motifs are essential biological components. Infrared (IR) spectroscopy is the premier tool to probe the OHO vibrations defining these structures, as vibrational frequencies directly reflect the underlying potential surface. Previously, infrared multiple photon dissociation (IRMPD) studies of deprotonated glutamic acid showed broad features, but their origin─thermal effects, multiple conformers, or intrinsic anharmonicity─remained unknown. To gain a better understanding, we utilized cryogenic ion spectroscopy at 4 K. We discovered that despite a single shared-proton conformer being dominant, broadband features persist, disappearing only upon deuteration. High-dimensional anharmonic calculations (27 modes) show that the OHO vibration is extensively coupled to combination bands and overtones of numerous low-frequency modes (700-1200 cm-1). This demonstrates that shared proton motion is intrinsically linked to the dynamics of the entire molecule rather than being an isolated vibration.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Chemistry, School of Science, Institute of Science Tokyo, Tokyo152-8550, Japan.",
    "Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei10617, Taiwan.",
    "Department of Chemistry, University of California, Berkeley, California94720, United States.",
    "Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California94720, United States.",
    "International Graduate Program of Molecular Science and Technology (NTU-MST), National Taiwan University, Taipei10617, Taiwan.",
    "Department of Chemistry, National Tsing Hua University, Hsinchu30013, Taiwan.",
    "Physics Division, National Center for Theoretical Sciences, Taipei10617, Taiwan."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 7,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Jun-Hao Yu",
      "orcid": "0009-0003-5719-108X"
    },
    {
      "affs": [
        0
      ],
      "name": "Shotaro Yoshikawa"
    },
    {
      "affs": [
        1
      ],
      "name": "Qian-Rui Huang"
    },
    {
      "affs": [
        0
      ],
      "name": "Keisuke Hirata"
    },
    {
      "affs": [
        2,
        3
      ],
      "name": "Daniel M Neumark",
      "orcid": "0000-0002-3762-9473"
    },
    {
      "affs": [
        1,
        4,
        5,
        6
      ],
      "name": "Jer-Lai Kuo"
    },
    {
      "affs": [
        0
      ],
      "name": "Shun-Ichi Ishiuchi",
      "orcid": "0000-0002-4079-818X"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/afgab7e54g91c.bib",
  "cited_by": 0,
  "doi": "10.1021/acs.jpclett.6c02479",
  "fulltext_url": "https://europepmc.org/articles/PMC13592069",
  "id": "afgab7e54g91c",
  "issns": [
    "1948-7185"
  ],
  "landing_url": "https://europepmc.org/article/MED/42915478",
  "language": "eng",
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "openalex",
      "3107|Spectroscopy and Quantum Chemical Studies"
    ]
  ],
  "openalex": "W7208769818",
  "pdf_url": "https://europepmc.org/articles/PMC13592069?pdf=render",
  "pmcid": "PMC13592069",
  "pmid": "42915478",
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/afgab7e54g91c.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:21:02Z",
      "native_id": "MED:42915478",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42915478"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "openalex:3107|Spectroscopy and Quantum Chemical Studies",
      "subfield": "amo"
    }
  ],
  "title": "Revealing Spectral Characteristics of Shared Protons in Deprotonated Glutamic Acid Using Cryogenic Ion Trap Spectroscopy and Anharmonic Calculations.",
  "title_text": "Revealing Spectral Characteristics of Shared Protons in Deprotonated Glutamic Acid Using Cryogenic Ion Trap Spectroscopy and Anharmonic Calculations.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:21:02Z",
  "url": "https://research.draconitic.com/paper/afgab7e54g91c",
  "venue": "The journal of physical chemistry letters",
  "versions": []
}