{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T13:17:07Z","timestamp":1785417427563,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T00:00:00Z","timestamp":1782259200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100006769","name":"Russian Science Foundation","doi-asserted-by":"publisher","award":["25-73-20122"],"award-info":[{"award-number":["25-73-20122"]}],"id":[{"id":"10.13039\/501100006769","id-type":"DOI","asserted-by":"publisher"}]},{"award":["25-73-20122"],"award-info":[{"award-number":["25-73-20122"]}],"id":[{"id":"https:\/\/ror.org\/03y2gwe85","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012190","name":"Ministry of Science and Higher Education of the Russian Federation","doi-asserted-by":"crossref","award":["075-03-2026-024"],"award-info":[{"award-number":["075-03-2026-024"]}],"id":[{"id":"10.13039\/501100012190","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>In this work, we report an example of tuning the photophysical properties of a polypyridine ruthenium(II) complex via the coordination of a second cation. A new ruthenium(II) complex contains a thiacrown-ether fragment that allows selective binding of additional metal cations (Ba2+, Cd2+, Pb2+), leading to pronounced changes in the optical and electronic properties of the bimetallic system. Spectroscopic and electrochemical studies reveal that the monoruthenium precursor displays dual excitation pathways involving either intraligand charge transfer (ILCT) or triplet metal-to-ligand charge transfer (3MLCT) excited states. Upon coordination of a second metal ion, the ILCT channel is suppressed, and only the 3MLCT state remains emissive, resulting in a significant increase in phosphorescence quantum yields (up to 22.6% in degassed solutions) for the bimetallic derivative. Time-resolved emission studies confirm the conversion from biexponential to monoexponential luminescence decay upon complexation. Electrochemical analysis and density functional theory (DFT) calculations support the hypothesis that cation binding alters the electron density distribution within the chromophore, stabilizing the MLCT pathway. These results demonstrate that incorporation of a second cation provides an effective strategy to control excited-state dynamics in ruthenium complexes, offering opportunities for the rational design of photosensitizers and photofunctional materials.<\/jats:p>","DOI":"10.3390\/molecules31132213","type":"journal-article","created":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T07:57:24Z","timestamp":1782287844000},"page":"2213","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Switching Between ILCT and 3MLCT Excited States by Complex Formation in Ruthenium\u2013Polypyridine Complex Containing Thiacrown-Ether Unit"],"prefix":"10.3390","volume":"31","author":[{"given":"Sergey","family":"Tokarev","sequence":"first","affiliation":[{"name":"A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6763-4145","authenticated-orcid":false,"given":"Anatoly","family":"Botezatu","sequence":"additional","affiliation":[{"name":"A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-4983-027X","authenticated-orcid":false,"given":"Daria","family":"Kharkovskaya","sequence":"additional","affiliation":[{"name":"A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2647-1439","authenticated-orcid":false,"given":"Gediminas","family":"Jonusauskas","sequence":"additional","affiliation":[{"name":"Laboratoire Ondes et Mati\u00e8re d\u2019Aquitaine\u2013UMR CNRS 5798, University of Bordeaux, 351 cours de la Lib\u00e9ration, 33405 Talence, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuri","family":"Fedorov","sequence":"additional","affiliation":[{"name":"A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Olga","family":"Fedorova","sequence":"additional","affiliation":[{"name":"A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 119334 Moscow, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1021\/ar980112j","article-title":"Molecular photovoltaics","volume":"33","author":"Hagfeldt","year":"2000","journal-title":"Acc. Chem. Res."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Balzani, V. (2001). Electron Transfer in Chemistry, Wiley-VCH.","DOI":"10.1002\/9783527618248"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"6232","DOI":"10.1021\/ja0259180","article-title":"Luminescence lifetime-based sensor for cyanide and related anions","volume":"124","author":"Anzenbacher","year":"2002","journal-title":"J. Am. Chem. 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