{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T22:25:41Z","timestamp":1783549541107,"version":"3.55.0"},"reference-count":44,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2023,2,18]],"date-time":"2023-02-18T00:00:00Z","timestamp":1676678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004007","name":"INFN Italy","doi-asserted-by":"publisher","award":["TERA"],"award-info":[{"award-number":["TERA"]}],"id":[{"id":"10.13039\/501100004007","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Using a customized time-domain ellipsometer operating in the THz range, the molecular dynamics of a liquid binary solution based on water and isopropyl alcohol (2-propanol) is investigated. The setup is capable of detecting small changes in the optical properties of the mixture within a single measurement. The complex dielectric response of samples with different concentrations is studied through the direct measurement of the ellipsometric parameters. The results are described using an effective Debye model, from which the relaxation parameters associated with different activation energies can be consistently extracted. Significant deviations between experimental data and the theoretical expectations at an intermediate volume percentage of 2-propanol in water are observed and interpreted as produced by competing effects: the creation\/destruction of hydrogen bonding on the one hand, and the presence of cluster\/aggregation between water and alcohol molecules on the other.<\/jats:p>","DOI":"10.3390\/s23042292","type":"journal-article","created":{"date-parts":[[2023,2,20]],"date-time":"2023-02-20T02:29:08Z","timestamp":1676860148000},"page":"2292","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Probing the Molecular Dynamics of Aqueous Binary Solutions with THz Time-Domain Ellipsometry"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1935-5034","authenticated-orcid":false,"given":"Zahra","family":"Mazaheri","sequence":"first","affiliation":[{"name":"Department of Physics \u201cE. Pancini\u201d, University of Naples Federico II, 80126 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2368-0064","authenticated-orcid":false,"given":"Gian Paolo","family":"Papari","sequence":"additional","affiliation":[{"name":"Department of Physics \u201cE. Pancini\u201d, University of Naples Federico II, 80126 Naples, Italy"},{"name":"Naples Unit, National Institute for Nuclear Physics, 80126 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6603-8162","authenticated-orcid":false,"given":"Antonello","family":"Andreone","sequence":"additional","affiliation":[{"name":"Department of Physics \u201cE. Pancini\u201d, University of Naples Federico II, 80126 Naples, Italy"},{"name":"Naples Unit, National Institute for Nuclear Physics, 80126 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"035346","DOI":"10.1063\/1.5082841","article-title":"Temperature dependent optical and dielectric properties of liquid water studied by terahertz time-domain spectroscopy","volume":"9","author":"Zhou","year":"2019","journal-title":"AIP Adv."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1016\/j.cplett.2013.11.055","article-title":"Ion effects on the structure of water studied by terahertz time-domain spectroscopy","volume":"591","author":"Kondoh","year":"2014","journal-title":"Chem. Phys. 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