Microgravity experiments confirm densest stable hard sphere crystal is most symmetric

Microgravity experiments confirm densest stable hard sphere crystal is most symmetric | 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 Physical Sciences - Article Microgravity experiments confirm densest stable hard sphere crystal is most symmetric Boris Khusid, Qian Lei, Andrew Hollingsworth, Paul Chaikin, William Meyer This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8536211/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract Packing of hard spheres fascinated mankind for millennia before it was also recognized as a versatile model for crystallization and other phenomena in materials. Theories in the 1930’s-60's predicted that they form a liquid phase for a particle volume fraction up to φ=0.494, a crystalline phase above φ =0.545 and coexistence in between1,2. In the mid 1980's, Pusey and van Megan confirmed this phase transition in colloids of closely matched particle/solvent densities3. However, their work and numerous experiments on Earth that followed observed small sedimented crystallites with random hexagonal close-packed (RHCP) structure and a high-density glass phase, in disagreement with theoretical predictions in the 1970’s-2020’s for high-symmetry faced-centered cubic (FCC) structure1,4,5. Here we report unique data with single-particle resolution on an FCC hard-sphere colloidal crystal, 27mm×1.2mm× 0.15 mm with φ ≈0.65, grown on the International Space Station. We confirm that FCC is the stable state for this most elementary system. The discovery that the absence of gravity makes it possible to equilibrate the FCC phase suggests routes for manufacturing colloidal crystals for mid-infrared photonics in a low-Earth orbit. Physical sciences/Materials science/Soft materials/Colloids Physical sciences/Materials science/Condensed-matter physics/Structure of solids and liquids Physical sciences/Materials science/Materials for optics/Photonic crystals Full Text Additional Declarations There is NO Competing Interest. Supplementary Files supplementaryFile3.docx Data on the particle arrangement in FCC crystal in sample C3. supplementaryFile4.docx Data on stacking faults with single-particle resolution in FCC crystal in sample C3 supplementaryinformationJan4QL.docx Supplementary Information SupplementaryFile1.mp4 Scan in X-direction in sample C3 SupplementaryFile2.mp4 3D rotatable image of FCC crystal in sample C3 Cite Share Download PDF Status: Under Review 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. 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