{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T12:57:35Z","timestamp":1791896255142,"version":"4.3.4"},"reference-count":52,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,5,26]],"date-time":"2023-05-26T00:00:00Z","timestamp":1685059200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000001","name":"USA National Science Foundation","doi-asserted-by":"publisher","award":["CHE 1800602"],"award-info":[{"award-number":["CHE 1800602"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"USA National Science Foundation","doi-asserted-by":"publisher","award":["CHE 2154609"],"award-info":[{"award-number":["CHE 2154609"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000001","name":"USA National Science Foundation","doi-asserted-by":"publisher","award":["60651-ND4"],"award-info":[{"award-number":["60651-ND4"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"name":"American Chemical Society Petroleum Research Fund","award":["CHE 1800602"],"award-info":[{"award-number":["CHE 1800602"]}]},{"name":"American Chemical Society Petroleum Research Fund","award":["CHE 2154609"],"award-info":[{"award-number":["CHE 2154609"]}]},{"name":"American Chemical Society Petroleum Research Fund","award":["60651-ND4"],"award-info":[{"award-number":["60651-ND4"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Medium polarity plays a crucial role in charge-transfer processes and electrochemistry. The added supporting electrolyte in electrochemical setups, essential for attaining the needed electrical conductivity, sets challenges for estimating medium polarity. Herein, we resort to Lippert\u2013Mataga\u2013Ooshika (LMO) formalism for estimating the Onsager polarity of electrolyte organic solutions pertinent to electrochemical analysis. An amine derivative of 1,8-naphthalimide proves to be an appropriate photoprobe for LMO analysis. An increase in electrolyte concentration enhances the polarity of the solutions. This effect becomes especially pronounced for low-polarity solvents. Adding 100 mM tetrabutylammonium hexafluorophosphate to chloroform results in solution polarity exceeding that of neat dichloromethane and 1,2-dichloroethane. Conversely, the observed polarity enhancement that emerges upon the same electrolyte addition to solvents such as acetonitrile and N,N-dimethylformamide is hardly as dramatic. Measured refractive indices provide a means for converting Onsager to Born polarity, which is essential for analyzing medium effects on electrochemical trends. This study demonstrates a robust optical means, encompassing steady-state spectroscopy and refractometry, for characterizing solution properties important for charge-transfer science and electrochemistry.<\/jats:p>","DOI":"10.3390\/molecules28114360","type":"journal-article","created":{"date-parts":[[2023,5,27]],"date-time":"2023-05-27T16:17:33Z","timestamp":1685204253000},"page":"4360","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Optical Window to Polarity of Electrolyte Solutions"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4742-4623","authenticated-orcid":false,"given":"Omar","family":"O\u2019Mari","sequence":"first","affiliation":[{"name":"Department of Bioengineering, University of California, Riverside, CA 92521, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3416-9686","authenticated-orcid":false,"given":"Valentine I.","family":"Vullev","sequence":"additional","affiliation":[{"name":"Department of Bioengineering, University of California, Riverside, CA 92521, USA"},{"name":"Department of Chemistry, University of California, Riverside, CA 92521, USA"},{"name":"Department of Biochemistry, University of California, Riverside, CA 92521, USA"},{"name":"Material Science and Engineering Program, University of California, Riverside, CA 92521, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"21583","DOI":"10.1039\/D0CP01556C","article-title":"Multifaceted aspects of charge transfer","volume":"22","author":"Derr","year":"2020","journal-title":"Phys. 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