{"paper_id":"2a737f96-3f8f-4e74-b166-2316de0b4d42","body_text":"Photochemically Induced Self-Healing in a Cadmium(II) Coordination Crystal | 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 Photochemically Induced Self-Healing in a Cadmium(II) Coordination Crystal Katherine Marczenko, Victoria Pham-Tran, Tristan LaCasse, Peter Gordon This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7925623/v2 This work is licensed under a CC BY 4.0 License Status: Posted Version 2 posted You are reading this latest preprint version Show more versions Abstract Self-healing in crystalline materials challenges the long-held perception of crystals as rigid and brittle. Here we report a new cadmium(II) coordination complex, Cd2(4-nvp)4(2-ohbz)4 (4-nvp = 4-(1-naphthyl)vinylpyridine, 2-ohbz = 2-hydroxybenzoate), that exhibits photochemical cracking, followed by autonomous repair under continuing ultraviolet irradiation. Upon 365 nm exposure for 3 min, [2 + 2] cycloaddition of olefinic ligands causes single crystals to fracture along {110} planes yet regain optical transparency and surface continuity within ~40 min under continued UV irradiation. Atomic-force microscopy reveals time-dependent smoothing of surface fracture topography, and diffraction techniques support recovery of bulk crystallinity. To our knowledge, this is the first example of a crystal that self-heals via a pericyclic, photochemical [2+2] reaction, wherein photodimerization provides both the trigger and the driving strain for reorganization of the crystal lattice and fissure closure at the microscopic scale. Physical sciences/Chemistry/Materials chemistry Physical sciences/Chemistry/Photochemistry Physical sciences/Chemistry/Coordination chemistry Physical sciences/Chemistry/Inorganic chemistry/Solid-state chemistry Full Text Additional Declarations The authors declare no competing interests. Supplementary Files MarczenkoSupportingPhotochemicallyInducedSelfHealing.pdf Supporting Information Cite Share Download PDF Status: Posted Version 2 posted You are reading this latest preprint version Show more versions 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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