Quantifying Superacidity with Density-Based Reactivity Theory

Quantifying Superacidity with Density-Based Reactivity Theory | 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 Quantifying Superacidity with Density-Based Reactivity Theory Yaqin Zheng, Xinyue Zhao, Lei Zeng, Chunying Rong, Shubin Liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7888421/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 16 Dec, 2025 Read the published version in Structural Chemistry → Version 1 posted 10 You are reading this latest preprint version Abstract Superacids, defined as compounds exhibiting acidities stronger than sulfuric acid, are essential in catalysis, synthesis, and material chemistry. Yet the quantitative understanding of their intrinsic acidity remains challenging due to the complex interplay of charge delocalization, resonance, and solvation effects. In this work, we employ density-based reactivity theory to describe and predict the equilibrium acidities of two major families of superacids—nitrogen-centered and carbon-centered species—each comprising multiple molecular series with experimentally measured pKₐ values available in 1,2-dichloroethane. Descriptors derived from conceptual density functional theory, information-theoretic approach, and topological analysis at bond critical points were systematically evaluated. Strong linear correlations between calculated descriptors and experimental pKₐ values were observed for N-centered superacids, confirming the robustness of density-based quantities in capturing intrinsic acidity. In contrast, weaker correlations for C-centered analogues reveal the multifaceted origins of their superacidity. Multi-descriptor regression further improves quantitative agreement across all systems. These findings demonstrate that superacidity is an emergent, electron density associated phenomenon that can be rationalized and predicted within the density-based reactivity framework. Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 16 Dec, 2025 Read the published version in Structural Chemistry → Version 1 posted Editorial decision: Revision requested 17 Nov, 2025 Reviews received at journal 15 Nov, 2025 Reviews received at journal 27 Oct, 2025 Reviewers agreed at journal 21 Oct, 2025 Reviewers agreed at journal 21 Oct, 2025 Reviewers agreed at journal 20 Oct, 2025 Reviewers invited by journal 20 Oct, 2025 Editor assigned by journal 20 Oct, 2025 Submission checks completed at journal 20 Oct, 2025 First submitted to journal 17 Oct, 2025 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. 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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-7888421","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":535699294,"identity":"37f64fa2-945f-4c18-bdd6-db0c150482e2","order_by":0,"name":"Yaqin Zheng","email":"","orcid":"","institution":"Hunan Normal University","correspondingAuthor":false,"prefix":"","firstName":"Yaqin","middleName":"","lastName":"Zheng","suffix":""},{"id":535699295,"identity":"8c83915e-f96f-4993-8f3a-f6b1fc6730eb","order_by":1,"name":"Xinyue Zhao","email":"","orcid":"","institution":"Hunan Normal 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Yet the quantitative understanding of their \u003cem\u003eintrinsic\u003c/em\u003e acidity remains challenging due to the complex interplay of charge delocalization, resonance, and solvation effects. In this work, we employ density-based reactivity theory to describe and predict the equilibrium acidities of two major families of superacids\u0026mdash;nitrogen-centered and carbon-centered species\u0026mdash;each comprising multiple molecular series with experimentally measured pKₐ values available in 1,2-dichloroethane. Descriptors derived from conceptual density functional theory, information-theoretic approach, and topological analysis at bond critical points were systematically evaluated. Strong linear correlations between calculated descriptors and experimental pKₐ values were observed for N-centered superacids, confirming the robustness of density-based quantities in capturing intrinsic acidity. In contrast, weaker correlations for C-centered analogues reveal the multifaceted origins of their superacidity. Multi-descriptor regression further improves quantitative agreement across all systems. These findings demonstrate that superacidity is an emergent, electron density associated phenomenon that can be rationalized and predicted within the density-based reactivity framework.\u003c/p\u003e","manuscriptTitle":"Quantifying Superacidity with Density-Based Reactivity Theory","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-31 06:50:51","doi":"10.21203/rs.3.rs-7888421/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-11-17T15:02:31+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-16T03:43:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-27T13:27:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"22264856765975588730316301879589965526","date":"2025-10-21T17:24:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"281952733986302843966708456680738371861","date":"2025-10-21T05:19:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"335982269368451870103053842274512605972","date":"2025-10-21T02:32:06+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-21T02:24:46+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-20T18:00:26+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-20T17:16:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"Structural Chemistry","date":"2025-10-17T16:08:31+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"structural-chemistry","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"stuc","sideBox":"Learn more about [Structural Chemistry](https://www.springer.com/journal/11224)","snPcode":"11224","submissionUrl":"https://submission.nature.com/new-submission/11224/3","title":"Structural Chemistry","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5a43d188-2abe-4424-8a87-ef78995c69d4","owner":[],"postedDate":"October 31st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-22T16:10:04+00:00","versionOfRecord":{"articleIdentity":"rs-7888421","link":"https://doi.org/10.1007/s11224-025-02695-0","journal":{"identity":"structural-chemistry","isVorOnly":false,"title":"Structural Chemistry"},"publishedOn":"2025-12-16 15:57:10","publishedOnDateReadable":"December 16th, 2025"},"versionCreatedAt":"2025-10-31 06:50:51","video":"","vorDoi":"10.1007/s11224-025-02695-0","vorDoiUrl":"https://doi.org/10.1007/s11224-025-02695-0","workflowStages":[]},"version":"v1","identity":"rs-7888421","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7888421","identity":"rs-7888421","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}