Very high frequency (263 GHz) pulse EPR spectroscopy of high spin transition metal centers

Very high frequency (263 GHz) pulse EPR spectroscopy of high spin transition metal centers | 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 Very high frequency (263 GHz) pulse EPR spectroscopy of high spin transition metal centers R. David Britt, Zikri Hasanbasri, Shasha Qiu, Guodong Rao, amanda Caceres, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7643135/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 Pulse Electron Paramagnetic Resonance (EPR) spectroscopy provides powerful tools for examining species with unpaired electrons, such as organic radicals and metal ions, in a wide variety of interesting systems. However, the lack of high power pulse amplifiers above approximately 100 GHz has limited its applicability at very high frequencies and magnetic fields. Here we describe the use of a new high frequency traveling wave vacuum tube amplifier employed in a pulse EPR spectrometer operating over a wide frequency bandwidth centered at 263 GHz. This novel instrument provides significant improvements in sensitivity and resolution when compared to lower frequency instruments. Very high frequency pulse EPR is of particular utility for studying spin S>1/2 species, given that large broadening effects of ``zero-field splitting'' interactions often dominate EPR spectra obtained at low frequency. Improvements obtained at 263 GHz are illustrated for a series of high spin (S=5/2) Mn(II) complexes. Physical sciences/Chemistry/Physical chemistry/Electron transfer Physical sciences/Chemistry/Inorganic chemistry Full Text Additional Declarations There is NO Competing Interest. Supplementary Files 263GHzSIFinal.pdf Supplementary Information for Very high frequency (263 GHz) pulse EPR spectroscopy of high spin transition metal centers 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. 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-7643135","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Physical Sciences - Article","associatedPublications":[],"authors":[{"id":517049224,"identity":"8b5f20fb-e626-4e1b-9a75-89bf6d0b0ac2","order_by":0,"name":"R. 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