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Hypervalent iron intermediates have been invoked in the catalytic cycles of many metalloproteins, and thus, it is crucial to understand how the coupling between such species and their environment can impact their chemical and physical properties in such contexts. In this work, we take advantage of the solvent kinetic isotope effect (SKIE) to gain insight into the nonradiative deactivation of electronic excited states of the aqueous ferrate(VI) ion. We observe an exceptionally large SKIE of 9.7 for the nanosecond-scale relaxation of the lowest energy triplet ligand field state to the ground state. Proton inventory studies demonstrate that a single solvent O–H bond is coupled to the ion during deactivation, likely due to the sparse vibrational structure of ferrate(VI). Such a mechanism is consistent with that reported for the deactivation of f–f excited states of aqueous trivalent lanthanides, which exhibit comparably large SKIE values. This phenomenon is ascribed entirely to dissipation of energy into a higher overtone of a solvent acceptor mode, as any impact on the apparent relaxation rate due to a change in solvent viscosity is negligible.
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Recent advances in hydrotropic solvent systems for lignocellulosic biomass utilization
Hydrotropic solvents are a promising solvent in biomass processing due to their unique amphiphilic structure. This review summarizes recent advances in hydrotropic solvent systems with their chemical structure, amphiphilicity, roles, and mechanism.
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- PAR ID:
- 10559298
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Green Chemistry
- Volume:
- 26
- Issue:
- 4
- ISSN:
- 1463-9262
- Page Range / eLocation ID:
- 1806 to 1830
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3GC03309K
