{"id":258821,"date":"2025-09-27T13:25:11","date_gmt":"2025-09-27T13:25:11","guid":{"rendered":"https:\/\/www.europesays.com\/us\/258821\/"},"modified":"2025-09-27T13:25:11","modified_gmt":"2025-09-27T13:25:11","slug":"softness-arises-from-hierarchical-structures","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/us\/258821\/","title":{"rendered":"Softness arises from hierarchical structures"},"content":{"rendered":"<p>            <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/09\/topology-reveals-the-h.jpg\" alt=\"Topology reveals the hidden rules of amorphous materials \u2014 Softness arises from hierarchical structures\" title=\"Summary of the present study Persistence diagram obtained from the structure of amorphous silicon, examples of the local ring structures corresponding to each point in the diagram, and representative structures including atoms with large nonaffine displacements. Credit: Emi Minamitani\" width=\"800\" height=\"530\"\/><\/p>\n<p>                Summary of the present study Persistence diagram obtained from the structure of amorphous silicon, examples of the local ring structures corresponding to each point in the diagram, and representative structures including atoms with large nonaffine displacements. Credit: Emi Minamitani<\/p>\n<p>Why do glass and other amorphous materials deform more easily in some regions than in others? A research team from the University of Osaka, the National Institute of Advanced Industrial Science and Technology (AIST), Okayama University, and the University of Tokyo has uncovered the answer.<\/p>\n<p>By applying a mathematical method known as persistent homology, the team demonstrated that these soft regions are governed by hidden hierarchical structures, where ordered and disordered <a href=\"https:\/\/phys.org\/tags\/atomic+arrangements\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">atomic arrangements<\/a> coexist.<\/p>\n<p>Crystalline solids, such as salt or ice, have atoms neatly arranged in repeating patterns. Amorphous materials, including glass, rubber, and certain plastics, lack this <a href=\"https:\/\/phys.org\/tags\/long-range+order\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">long-range order<\/a>. However, they are not completely random: they possess medium-range order (MRO), subtle atomic patterns that extend over a few nanometers.<\/p>\n<p>MRO has long been suspected to play a critical role in determining the physical properties of <a href=\"https:\/\/phys.org\/tags\/amorphous+materials\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">amorphous materials<\/a>, particularly their mechanical responses. Yet, because of the complexity of atomic networks, conventional analysis methods have been unable to clarify how MRO relates to regions that deform more easily than their surroundings. The structural origins of mechanical softness in amorphous solids have therefore remained elusive.<\/p>\n<p>The research team applied persistent homology, a branch of topological data analysis that captures structural features across multiple scales. In <a href=\"https:\/\/phys.org\/tags\/amorphous+silicon\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">amorphous silicon<\/a>\u2014a prototypical covalent amorphous material widely used in <a href=\"https:\/\/phys.org\/tags\/solar+cells\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">solar cells<\/a> and electronic devices\u2014they discovered hierarchical ring structures: smaller rings with irregular edge lengths are nested inside larger rings.<\/p>\n<p>This coexistence of order and disorder means that softness emerges not from randomness alone, but from constraints imposed by medium-range order interwoven with local disorder. The study also revealed that these <a href=\"https:\/\/phys.org\/tags\/hierarchical+structures\/\" rel=\"tag nofollow noopener\" class=\"textTag\" target=\"_blank\">hierarchical structures<\/a> strongly correlate with low-energy localized vibrations, a universal feature of glasses known as the &#8220;boson peak.&#8221;<\/p>\n<p>&#8220;This work provides a new route to link the atomic structure of amorphous materials with their mechanical responses,&#8221; says Emi Minamitani of the University of Osaka, the lead author of the study published in Nature Communications.<\/p>\n<p>&#8220;We believe these insights will accelerate the design of durable glass and other advanced amorphous materials.&#8221;<\/p>\n<p>The discovery establishes a clear structural principle: mechanically soft regions arise where disorder is embedded within medium-range order.<\/p>\n<p>This counterintuitive finding provides a practical guideline for developing amorphous solids that are both flexible and strong\u2014benefiting applications from displays and coatings to energy devices.<\/p>\n<p><strong>More information:<\/strong><br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tPersistent homology elucidates hierarchical structures responsible for mechanical properties in covalent amorphous solids, Nature Communications (2025). <a data-doi=\"1\" href=\"https:\/\/dx.doi.org\/10.1038\/s41467-025-63424-z\" target=\"_blank\" rel=\"nofollow noopener\">DOI: 10.1038\/s41467-025-63424-z<\/a><\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t\t\tProvided by<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a href=\"https:\/\/phys.org\/partners\/university-of-osaka\/\" rel=\"nofollow noopener\" target=\"_blank\">University of Osaka<\/a><br \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"icon_open\" href=\"https:\/\/www.osaka-u.ac.jp\/en\" target=\"_blank\" rel=\"nofollow noopener\"><\/p>\n<p>\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t\t<strong>Citation<\/strong>:<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tTopology reveals the hidden rules of amorphous materials: Softness arises from hierarchical structures (2025, September 25)<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tretrieved 27 September 2025<br \/>\n\t\t\t\t\t\t\t\t\t\t\t\tfrom https:\/\/phys.org\/news\/2025-09-topology-reveals-hidden-amorphous-materials.html\n\t\t\t\t\t\t\t\t\t\t\t <\/p>\n<p>\n\t\t\t\t\t\t\t\t\t\t\t This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no<br \/>\n\t\t\t\t\t\t\t\t\t\t\t part may be reproduced without the written permission. The content is provided for information purposes only.\n\t\t\t\t\t\t\t\t\t\t\t <\/p>\n","protected":false},"excerpt":{"rendered":"Summary of the present study Persistence diagram obtained from the structure of amorphous silicon, examples of the local&hellip;\n","protected":false},"author":3,"featured_media":258822,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[25],"tags":[493,494,492,489,159,490,158,491,67,132,68],"class_list":{"0":"post-258821","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-materials","9":"tag-nanotech","10":"tag-physics","11":"tag-physics-news","12":"tag-science","13":"tag-science-news","14":"tag-technology","15":"tag-technology-news","16":"tag-united-states","17":"tag-unitedstates","18":"tag-us"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@us\/115276488685915287","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/258821","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/comments?post=258821"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/posts\/258821\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media\/258822"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/media?parent=258821"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/categories?post=258821"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/us\/wp-json\/wp\/v2\/tags?post=258821"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}