Stability of the local electronic properties of La3Ni2O7 under pressure

Stability of the local electronic properties of La3Ni2O7 under pressure | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Stability of the local electronic properties of La3Ni2O7 under pressure Emin Mijit This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7347905/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Motivated by the recent discovery of superconductivity in bulk La3Ni2O7 under pressure, we investigated its local electronic structure—specifically the Ni oxidation state, 3d occupancy, spin configuration, and 3d − 2p hybridization—using Ni K-edge x-ray absorption spectroscopy (XAS) and Kβ x-ray emission spectroscopy (XES), complemented by density functional theory (DFT) and spectral simulations. Despite the average valence of ∼2.5+ indicated by XAS, analysis of the XES spectra revealed 3d8L electronic configuration with low-spin ground state. Under HP up to 30 GPa and low T down to 10 K, we find no evidence of changes in Ni valence, 3d occupancy, or spin state, effectively ruling out pressure-induced spin-state transitions proposed in some theoretical models. Additional La L3-edge XAS measurements show only subtle spectral modifications, inconsistent with significant 3d−5d charge transfer. These results suggest that the pressure-induced superconductivity in La3Ni2O7 is unlikely linked with substantial changes in the local electronic structure. Physical sciences/Physics/Condensed-matter physics/Superconducting properties and materials Physical sciences/Physics/Condensed-matter physics/Electronic properties and materials Full Text Additional Declarations There is NO Competing Interest. Supplementary Files Supplementaryinformation.pdf Stability of local electronic properties in La3Ni2O7 under pressure Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7347905","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":507107460,"identity":"de859c1b-d8e0-4396-b214-142b99af148b","order_by":0,"name":"Emin Mijit","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6klEQVRIiWNgGAWjYFACxgYgIcHMBiQP/6kAkszMDURqYWNgPMBzBqSFkZAWGGBjYD7A2wY3BDfgFzvc9oAxx4KdT76B4YDkvNpo/naglh8V23BqkZyd2G7AuA3sMIYDhtuO5844zNjA2HPmNk4tBrcT2yTgWhK3HcttAGphZmzDrcUeRcvBOcdy5xPSYiCNpOVgY0NN7gZCWiRAtiSCtSQ2HGY4diB3I1DLQXx+4Z+d/kzi47a6ZPnmw4c/M9TU5c47f/jggx8VuLWAQQIDQzI0Og6DBQ7gVw8BdlC6jhjFo2AUjIJRMMIAAO4RVAiH59zqAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0002-9232-2538","institution":"European Synchrotron Radiation Facility","correspondingAuthor":true,"prefix":"","firstName":"Emin","middleName":"","lastName":"Mijit","suffix":""}],"badges":[],"createdAt":"2025-08-11 15:36:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7347905/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7347905/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107481442,"identity":"ac7665d8-2780-4bda-9410-2b5696cb5b83","added_by":"auto","created_at":"2026-04-22 02:17:59","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":353742,"visible":true,"origin":"","legend":"Article File","description":"","filename":"Manuscriptmaintext.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7347905/v1_covered_60e8a87f-b0dd-4053-961e-98ed92808d60.pdf"},{"id":90282034,"identity":"a3eaed75-2786-4b6c-b1ca-fd8c77b2524e","added_by":"auto","created_at":"2025-09-01 05:06:56","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":439486,"visible":true,"origin":"","legend":"Stability of local electronic properties in La3Ni2O7 under pressure","description":"","filename":"Supplementaryinformation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7347905/v1/ef198807455a358475802a7d.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Stability of the local electronic properties of La3Ni2O7 under pressure","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7347905/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7347905/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Motivated by the recent discovery of superconductivity in bulk La3Ni2O7 under pressure, we\r\ninvestigated its local electronic structure—specifically the Ni oxidation state, 3d occupancy, spin\r\nconfiguration, and 3d − 2p hybridization—using Ni K-edge x-ray absorption spectroscopy (XAS)\r\nand Kβ x-ray emission spectroscopy (XES), complemented by density functional theory (DFT) and\r\nspectral simulations. Despite the average valence of ∼2.5+ indicated by XAS, analysis of the XES\r\nspectra revealed 3d8L electronic configuration with low-spin ground state. Under HP up to 30 GPa\r\nand low T down to 10 K, we find no evidence of changes in Ni valence, 3d occupancy, or spin state,\r\neffectively ruling out pressure-induced spin-state transitions proposed in some theoretical models.\r\nAdditional La L3-edge XAS measurements show only subtle spectral modifications, inconsistent with\r\nsignificant 3d−5d charge transfer. These results suggest that the pressure-induced superconductivity\r\nin La3Ni2O7 is unlikely linked with substantial changes in the local electronic structure.","manuscriptTitle":"Stability of the local electronic properties of La3Ni2O7 under pressure","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-01 05:06:51","doi":"10.21203/rs.3.rs-7347905/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3535f19c-063e-4de1-8693-074f5c01a500","owner":[],"postedDate":"September 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":53867444,"name":"Physical sciences/Physics/Condensed-matter physics/Superconducting properties and materials"},{"id":53867445,"name":"Physical sciences/Physics/Condensed-matter physics/Electronic properties and materials"}],"tags":[],"updatedAt":"2026-04-15T17:05:47+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-01 05:06:51","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7347905","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7347905","identity":"rs-7347905","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}