{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,8]],"date-time":"2026-01-08T20:18:25Z","timestamp":1767903505907,"version":"3.49.0"},"reference-count":35,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T00:00:00Z","timestamp":1701216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fonds der Chemischen Industrie (FCI) im Verband der Chemischen Industrie e.V","award":["K 212\/14"],"award-info":[{"award-number":["K 212\/14"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Organic\u2013inorganic halocuprates based on monovalent copper are promising luminescent compounds for optoelectronic applications; however, their relaxation processes in the excited electronic state are severely underexplored. In this contribution, we prepare thin films of bis(tetraethylammonium) di-\u00b5-bromo-dibromodicuprate(I) [N(C2H5)4]2[Cu2Br4], abbreviated (TEA)2Cu2Br4, which features a \u201cmolecular salt\u201d structure containing discrete [Cu2Br4]2\u2212 anions. This compound, which has an absorption peak at 283 nm, displays a blue, strongly Stokes-shifted emission with a peak at 467 nm. Transient photoluminescence (PL) experiments using broadband emission detection and time-correlated single-photon counting (TCSPC) both find an excited-state lifetime of 57 \u03bcs at 296 K. UV\u2013Vis transient absorption experiments at 296 K covering time scales from femto- to microseconds provide evidence for the formation of the T1 state through intersystem crossing from S1 with a time constant of 184 ps. The triplet state subsequently decays to S0 predominantly by phosphorescence. In addition, the time constants for carrier\u2013optical phonon scattering (1.8 ps) and acoustic phonon relaxation (8.3 ns and 465 ns) of (TEA)2Cu2Br4 are provided.<\/jats:p>","DOI":"10.3390\/molecules28237841","type":"journal-article","created":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T03:53:52Z","timestamp":1701230032000},"page":"7841","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Excited-State Dynamics of Bis(tetraethylammonium) Di-\u00b5-bromo-dibromodicuprate(I) Thin Films"],"prefix":"10.3390","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0009-0002-7999-4150","authenticated-orcid":false,"given":"Domenic","family":"Gust","sequence":"first","affiliation":[{"name":"Physical Chemistry 2, Department Chemistry and Biology, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5648-7925","authenticated-orcid":false,"given":"Mirko","family":"Scholz","sequence":"additional","affiliation":[{"name":"Physical Chemistry 2, Department Chemistry and Biology, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6137-2236","authenticated-orcid":false,"given":"Kawon","family":"Oum","sequence":"additional","affiliation":[{"name":"Physical Chemistry 2, Department Chemistry and Biology, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0766-709X","authenticated-orcid":false,"given":"Thomas","family":"Lenzer","sequence":"additional","affiliation":[{"name":"Physical Chemistry 2, Department Chemistry and Biology, Faculty IV: School of Science and Technology, University of Siegen, Adolf-Reichwein-Str. 2, 57076 Siegen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3364","DOI":"10.1021\/acs.chemmater.3c00071","article-title":"Ultrabright Light Emission Properties of All-Inorganic and Hybrid Organic\u2212Inorganic Copper(I) Halides","volume":"35","author":"Banerjee","year":"2023","journal-title":"Chem. 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