{
  "abstract": "External parameters such as temperature, pressure, and chemical doping can induce structural phase transitions in materials. Although such transitions usually involve a change in symmetry, an uncommon exception is the isostructural phase transition, which is first order yet preserves the symmetry of the parent structure. Using first-principles calculations, we show that $AM_2$Al$_9$ compounds ($A$ = Ba, Ca, Sr, or Eu; $M$ = Fe, Co, or Ni) undergo pressure-induced isostructural phase transitions. At the transition pressure, these systems exhibit a pronounced volume collapse while retaining the same crystal symmetry and space group ($P6/mmm$). Bonding analysis based on the integrated crystal orbital Hamilton population (ICOHP) shows that the transition is driven by a redistribution of bonding character between intralayer and interlayer atomic bonds. Because isostructural transitions are rare in single crystals, $AM_2$Al$_9$ provides a promising platform for investigating critical phenomena under pressure and for deepening our understanding of symmetry-preserving structural transitions.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2608.28957",
  "author_total": 4,
  "authors": [
    {
      "name": "Jian-Feng Zhang"
    },
    {
      "name": "Sheng Xu"
    },
    {
      "name": "Zhong-Yi Lu"
    },
    {
      "name": "Tao Xiang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/bpg0bnyzx3ctg.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2608.28957",
  "fulltext_url": null,
  "id": "bpg0bnyzx3ctg",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2608.28957",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.mtrl-sci"
    ],
    [
      "openalex",
      "1908|High-pressure geophysics and materials"
    ]
  ],
  "openalex": "W7204964760",
  "pdf_url": "https://arxiv.org/pdf/2608.28957",
  "pmcid": null,
  "pmid": null,
  "published": "2026-08-29",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/bpg0bnyzx3ctg.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:41Z",
      "native_id": "2608.28957",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2608.28957"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.mtrl-sci",
      "subfield": "condensed-matter"
    }
  ],
  "title": "Symmetry-Preserving Phase Transitions in $AM_2$Al$_9$ Materials under Pressure",
  "title_text": "Symmetry-Preserving Phase Transitions in AM_2Al_9 Materials under Pressure",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:41Z",
  "url": "https://research.draconitic.com/paper/bpg0bnyzx3ctg",
  "venue": "arXiv",
  "versions": []
}