Coupling experiment and theory to push the state-of-the-art in X-ray spectroscopy | Nature Reviews Chemistry

Jun 04, 2025

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X-ray spectroscopy plays a pivotal role in understanding the geometric and electronic structures of countless molecules and materials, from homogeneous and heterogeneous catalysts to biological active sites. The element-selectivity of X-ray spectroscopy allows for phenomena at specific photoabsorbers to be investigated. Since the early 2000s, experimental sophistication has progressed, with increasing applications of X-ray emission spectroscopy and two-dimensional photon-in-photon-out spectroscopies, such as resonant inelastic X-ray scattering. Although advanced X-ray spectroscopic methods increase selectivity and information content, the spectra obtained present major challenges for both qualitative and quantitative interpretation. To maximize the insight gained from X-ray spectroscopy, close coupling of experiment and theory is essential. Herein, we present the theoretical and experimental aspects of X-ray spectroscopy, with an emphasis on molecular systems and how an integrated approach with a solid foundation in molecular electronic structure theory enables new modes of inquiry into (bio)chemical catalysis.

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The authors thank the Max Planck Society for funding. The authors thank R. Shafei for assistance with L-edge calculations.

Department of Inorganic Spectroscopy, Max Planck Institute for Chemical Energy Conversion, Mülheim an der Ruhr, Germany

Zachary Mathe & Serena DeBeer

Department of Molecular Theory and Spectroscopy, Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany

Dimitrios Maganas & Frank Neese

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S.D. and F.N. conceived the idea. Z.M. wrote the original draft. All authors contributed substantially to the discussion and revision of the manuscript.

Correspondence to Frank Neese or Serena DeBeer.

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Nature Reviews Chemistry thanks Frank de Groot and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Mathe, Z., Maganas, D., Neese, F. et al. Coupling experiment and theory to push the state-of-the-art in X-ray spectroscopy. Nat Rev Chem (2025). https://doi.org/10.1038/s41570-025-00718-2

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Accepted: 08 April 2025

Published: 30 May 2025

DOI: https://doi.org/10.1038/s41570-025-00718-2

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