Novel hyperdense orthorhombic C10 with ultrahigh hardness, and physical properties close to Diamond: Crystal chemistry and DFT investigations.

Novel hyperdense orthorhombic C10 with ultrahigh hardness, and physical properties close to Diamond: Crystal chemistry and DFT investigations. | 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 Novel hyperdense orthorhombic C10 with ultrahigh hardness, and physical properties close to Diamond: Crystal chemistry and DFT investigations. Samir F. Matar This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8108306/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 Based on crystal chemistry search and density functional theory (DFT), an original orthorhombic C 10 allotrope is proposed with ultra-high density of 3.75 g/cm 3 (versus 3.54 g/cm 3 for diamond) and ultra-high Vickers hardness (H V = 100 GPa versus 95 GPa for Diamond). Such properties pertain to the exceptional arrangement of distorted C4 tetrahedra connected by short d(C-C) = 1.51 Å, opposite to diamond characterized by corner sharing tetrahedra. The resulting structure has unknown topology. Phonon band structures show highest optic modes of 40 THz close to experimental diamond Raman line. The calculated specific heat C V curve shows shape agreement with experimental diamond values. The electronic band structure exhibits indirect band gap of 3 eV confirming semi-conducting C 10 versus insulating diamond. DFT Diamond crystal chemistrty phonons density hardness Full Text Additional Declarations No competing interests reported. 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-8108306","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":546477071,"identity":"38679a87-215b-4775-87c5-d8886eb61c1e","order_by":0,"name":"Samir F. 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