The metal centres in metalloenzymes and molecular catalysts are responsible for the rearrangement of atoms and electrons during complex chemical reactions, and they enable selective pathways of charge and spin transfer, bond breaking/making and the formation of new molecules. Mapping the electronic structural changes at the metal sites during the reactions gives a unique mechanistic insight that has been difficult to obtain to date. The development of X-ray free-electron lasers (XFELs) enables powerful new probes of electronic structure dynamics to advance our understanding of metalloenzymes. The ultrashort, intense and tunable XFEL pulses enable X-ray spectroscopic studies of metalloenzymes, molecular catalysts and chemical reactions, under functional conditions and in real time. In this Technical Review, we describe the current state of the art of X-ray spectroscopy studies at XFELs and highlight some new techniques currently under development. With more XFEL facilities starting operation and more in the planning or construction phase, new capabilities are expected, including high repetition rate, better XFEL pulse control and advanced instrumentation. For the first time, it will be possible to make real-time molecular movies of metalloenzymes and catalysts in solution, while chemical reactions are taking place.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8245202 | PMC |
http://dx.doi.org/10.1038/s42254-021-00289-3 | DOI Listing |
Small
January 2025
School of Materials and Chemistry, University of Shanghai for Science and Technology, Shanghai, 200093, P. R. China.
Chlorophenols are difficult to degrade and mineralize by traditional advanced oxidation processes due to the strong electronegativity of chlorine. Here, a dual-site atomically dispersed catalyst (FeMoNC) is reported, which Fe/Mo supported on mesoporous nitrogen-doped carbon is prepared through high-temperature migration. The FeMoNC exhibits a high dechlorination rate of 93.
View Article and Find Full Text PDFSmall Methods
January 2025
Institute of Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1, Zürich, 8093, Switzerland.
In situ monitoring is essential for catalytic process design, offering real-time insights into active structures and reactive intermediates. Electron paramagnetic resonance (EPR) spectroscopy excels at probing geometric and electronic properties of paramagnetic species during reactions. Yet, state-of-the-art liquid-phase EPR methods, like flat cells, require custom resonators, consume large amounts of reagents, and are unsuited for tracking initial kinetics or use with solid catalysts.
View Article and Find Full Text PDFJ Phys Chem C Nanomater Interfaces
January 2025
Materials Chemistry and Catalysis, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht 3584 CG, The Netherlands.
Machine learning potentials (MLPs) offer efficient and accurate material simulations, but constructing the reference ab initio database remains a significant challenge, particularly for catalyst-adsorbate systems. Training an MLP with a small data set can lead to overfitting, thus limiting its practical applications. This study explores the feasibility of developing computationally cost-effective and accurate MLPs for catalyst-adsorbate systems with a limited number of ab initio references by leveraging a transfer learning strategy from subsets of a comprehensive public database.
View Article and Find Full Text PDFChem Sci
January 2025
Department of Chemistry, Indian Institute of Technology Hauz Khas Delhi New Delhi 110016 India
The direct transformation of methane into C oxygenates such as acetic acid selectively using molecular oxygen (O) is a significant challenge due to the chemical inertness of methane, the difficulty of methane C-H bond activation/C-C bond coupling and the thermodynamically favored over-oxidation. In this study, we have successfully developed a porous aluminium metal-organic framework (MOF)-supported single-site mono-copper(ii) hydroxyl catalyst [MIL-53(Al)-Cu(OH)], which is efficient in directly oxidizing methane to acetic acid in water at 175 °C with a remarkable selectivity using only O. This heterogeneous catalyst achieved an exceptional acetic acid productivity of 11 796 mmol mol h in 9.
View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany.
Identification of rate determining steps concerning catalyst activation and catalytic turnover is key to optimize molecular photocatalysts. In this contribution, femtosecond transient absorption spectroscopy upon variation of temperature and ionic strength yields new insights into the light-driven reactivity of the benchmark molecular photocatalyst, RutpphzRhCp*.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!