Kagome Electride Superconductors Under Extreme Conditions

Kagome Electride Superconductors Under Extreme Conditions | 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 Research Article Kagome Electride Superconductors Under Extreme Conditions Edison Zacarias da Silva, Zenner S. Pereira, Luis Cabral This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8631682/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 20 Mar, 2026 Read the published version in Brazilian Journal of Physics → Version 1 posted You are reading this latest preprint version Abstract We investigate pressure-induced superconductivity in the electride compound Li5C and in elemental ω-Hf using density functional theory (DFT) combined with Migdal–Eliashberg theory. Despite their distinct chemistry, both systems become superconducting under compression and share a key ingredient: an electride state in which interstitial anionic electrons organize into a two-dimensional kagome topology embedded in the ionic lattice. Li5C has been proposed as a kagome-electride superconductor in the pressure range 50–210 GPa, reaching a maximum transition temperature of Tc = 48.3 K at 210 GPa, whereas pure Hf develops electride character in the 40–60 GPa regime of the high-pressure ω phase. Motivated by these developments, we first revisit Li5C and emphasize the importance of the electride state for its superconducting response. We then identify analogous kagome-electride features in ω-Hf and analyze their role in the superconductivity of compressed Hf. For ω-Hf, we show that spin–orbit coupling (SOC), which is significant in this d-band transition metal, acts in concert with electride-derived states near the Fermi level to enhance the electron–phonon coupling. This interplay provides a consistent microscopic picture of the superconducting phase and yields transition temperatures in very good agreement with previously reported experimental data. Electrides kagome lattice superconductivity interstitial electrons high pressure electron–phonon coupling Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 20 Mar, 2026 Read the published version in Brazilian Journal of Physics → 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. 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