Excitation Wavelength Dependent O 2 Release from Copper(II)–Superoxide Compounds: Laser Flash-Photolysis Experiments and Theoretical Studies
In: Journal of the American Chemical Society, 2014
Online
academicJournal
Zugriff:
Irradiation of the copper(II)–superoxide synthetic complexes [(TMG 3 tren)Cu II (O 2 )] + (1) and [(PV-TMPA)Cu II (O 2 )] + (2) with visible light resulted in direct photogeneration of O 2 gas at low temperature (from −40 °C to −70 °C for 1 and from −125 to −135 °C for 2) in 2-methyltetrahydrofuran (MeTHF) solvent. The yield of O 2 release was wavelength dependent: λ exc = 436 nm, ϕ = 0.29 (for 1), ϕ = 0.11 (for 2), and λ exc = 683 nm, ϕ = 0.035 (for 1), ϕ = 0.078 (for 2), which was followed by fast O 2 -recombination with [(TMG 3 tren)Cu I ] + (3) and [(PV-TMPA)Cu I ] + (4). Enthalpic barriers for O 2 rebinding to the copper(I) center (∼10 kJ mol –1 ) and for O 2 dissociation from the superoxide compound 1 (45 kJ mol –1 ) were determined. TD-DFT studies, carried out for 1, support the experimental results confirming the dissociative character of the excited states formed upon blue- or red-light laser excitation.
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Excitation Wavelength Dependent O 2 Release from Copper(II)–Superoxide Compounds: Laser Flash-Photolysis Experiments and Theoretical Studies
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Autor/in / Beteiligte Person: | Saracini, C. ; Liakos, D. ; Zapata Rivera, J. ; Neese, F. ; Meyer, G. ; Karlin, K. |
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Zeitschrift: | Journal of the American Chemical Society, 2014 |
Veröffentlichung: | 2014 |
Medientyp: | academicJournal |
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