Synthesis and Photophysical Properties of a Series of Dimeric Indium Quinolinates

• Published in: Molecules (Basel, Switzerland) Vol. 26; no. 1; p. 34
• Main Authors: Kwak, Sang Woo, Hong, Ju Hyun, Lee, Sanghun, Kim, Min, Chung, Yongseog, Lee, Kang Mun, Kim, Youngjo, Park, Myung Hwan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 23.12.2020; MDPI AG
• Subjects: charge transfer; Indium - chemistry; indium quinolinates; Models, Molecular; Molecular Structure; non-radiative constant; Photochemical Processes; Quantum Theory; quantum yield; Quinolinic Acid - chemical synthesis; radiative decay constant; Solvents - chemistry; indium quinolinates; non-radiative constant; radiative decay constant; quantum yield; charge transfer
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/MOLECULES26010034

A novel class of quinolinol-based dimeric indium complexes ( - ) was synthesized and characterized using H and C( H) NMR spectroscopy and elemental analysis. Compounds - exhibited typical low-energy absorption bands assignable to quinolinol-centered π-π* charge transfer (CT) transition. The emission spectra of - exhibited slight bathochromic shifts with increasing solvent polarity ( -xylene < tetrahydrofuran (THF) < dichloromethane (DCM)). The emission bands also showed a gradual redshift, with an increase in the electron-donating effect of substituents at the C5 position of the quinoline groups. The absolute emission quantum yields (Φ ) of compounds (11.2% in THF and 17.2% in film) and (17.8% in THF and 36.2% in film) with methyl substituents at the C5 position of the quinoline moieties were higher than those of the indium complexes with other substituents.