Induction of J Aggregate-like Optical Transitions in Dihydroxyquinone by Coordination with Al(III).

ABSTRACT: The metal-complex formation of 1,4-dihydroxyanthraquinone (quinizarin, QNZ) and 6,11-dihydroxy-5,12-naphthacenedione (DHN) with Al(III) ions is investigated by stationary and time-resolved emission spectroscopy combined with quantum chemical calculations of optical properties. UV-vis and fluorescence spectra revealed small red-shifts of 200 and 60 meV for the QNZ and DHN metal complexes, respectively. The fluorescence quantum yield increases from 0.08 to 0.23 for QNZ, while for DHN it changes from 0.24 to 0.79 upon complexation, suggesting the presence of J-aggregate-like exciton coupling within the coordination structure. The average fluorescence lifetime of QNZ varies from 0.65 ns of the free ligand to 2.77 ns, and in the case of DHN it goes from 1.57 to 2.61 ns after Al(III) complexatio

SUBMITTER: Granado Neto JR 

PROVIDER: S-EPMC12908156 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature