Synthesis, Structure, and Optical Properties of Cyclometalated Iridium(III) Complexes with 2-Arylbenzimidazoles and Pyrazino[2,3-f][1,10]phenanthroline
{"title":"Synthesis, Structure, and Optical Properties of Cyclometalated Iridium(III) Complexes with 2-Arylbenzimidazoles and Pyrazino[2,3-f][1,10]phenanthroline","authors":"E. A. Sholina, S. I. Bezzubov","doi":"10.1134/S1070328425600573","DOIUrl":null,"url":null,"abstract":"<p>Two new iridium(III) complexes with benzimidazole ligands differing in the size of the aromatic system and an auxiliary N-donor ligand with an extended conjugated system were synthesized and studied by structural and spectroscopic methods. A comparison of the results of crystal packing analysis with the data of electronic absorption spectroscopy, diffuse reflectance spectroscopy, and luminescence spectroscopy shows that intermolecular π–π interactions between the benzimidazole ligands have little effect on the optical characteristics of the complexes. Both compounds exhibit light absorption in the 250–550 nm range (ε = 58 000–1000 M<sup>–1</sup> cm<sup>–1</sup>) in solution and in the solid state (<i>E</i><sub>g</sub> = 2.14–2.16 eV) and emit in the orange region (λ<sub>max</sub> = 558–585 nm), with the maxima of solid-state emission systematically red-shifted by approximately 25 nm compared to emission in solution. The results of this work provide a better understanding of the extent to which crystal packing affects the optical properties of iridium(III) complexes and will be used in further development of crystal engineering approaches for designing iridium-based luminescent compounds in the long-wavelength region.</p>","PeriodicalId":759,"journal":{"name":"Russian Journal of Coordination Chemistry","volume":"51 6","pages":"455 - 463"},"PeriodicalIF":1.1000,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Russian Journal of Coordination Chemistry","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1134/S1070328425600573","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
Two new iridium(III) complexes with benzimidazole ligands differing in the size of the aromatic system and an auxiliary N-donor ligand with an extended conjugated system were synthesized and studied by structural and spectroscopic methods. A comparison of the results of crystal packing analysis with the data of electronic absorption spectroscopy, diffuse reflectance spectroscopy, and luminescence spectroscopy shows that intermolecular π–π interactions between the benzimidazole ligands have little effect on the optical characteristics of the complexes. Both compounds exhibit light absorption in the 250–550 nm range (ε = 58 000–1000 M–1 cm–1) in solution and in the solid state (Eg = 2.14–2.16 eV) and emit in the orange region (λmax = 558–585 nm), with the maxima of solid-state emission systematically red-shifted by approximately 25 nm compared to emission in solution. The results of this work provide a better understanding of the extent to which crystal packing affects the optical properties of iridium(III) complexes and will be used in further development of crystal engineering approaches for designing iridium-based luminescent compounds in the long-wavelength region.
期刊介绍:
Russian Journal of Coordination Chemistry is a journal that publishes reviews, original papers, and short communications on all aspects of theoretical and experimental coordination chemistry. Modern coordination chemistry is an interdisciplinary science that makes a bridge between inorganic, organic, physical, analytical, and biological chemistry.