Shedding light on the hidden world of actinide bonding and behavior using photon spectro-microscopy

Characteristics of radionuclides—such as the spontaneous emission of radiation or the induced fission of heavy nuclei—are utilized in various fields, including medicine, science, and energy production. These radionuclides are often actinides, whose electronic structure and bonding behavior with other elements—both fundamentally and in environmental and biological systems—are still not fully understood. Spectroscopies involving the ionization or excitation of core electrons, such as X-ray absorption/emission spectroscopy (XAS, XES) and resonant inelastic X-ray scattering (RIXS), can help address these questions. For example, newly identified and interpreted satellite features in RIXS maps provide insights into the localized and delocalized aspects of the electronic structure [1]. Additionally, X-rays and gamma photons emitted during radioactive decay can aid in elucidating daughter nuclide distribution and bonding, which is relevant for future applications in nuclear medicine. Here, I will present initial steps toward visualizing these processes using newly developed, specialized detectors based on Magnetic Metallic Calorimeters (MMCs) [2]. ... mehrBeyond spectroscopic information, it is also possible to visualize the localization of radionuclides—down to the nanometer scale in human cells—using spectro-microscopic techniques such as scanning transmission X-ray microscopy (STXM). I will demonstrate how the development and application of specialized methods and concepts in radiochemistry can shed light on these fascinating and fundamental questions [3].

Literature:
[1] Schacherl, B. et al. Nat. Commun. 2025, 16, 1, 1221.
[2] Maurer, K. et al. Towards Cancer Theragnostic ‒ Probing the 225Ac decay chain with Ultra-High-Resolution MMC-based detectors, submitted.
[3] Schacherl, B. et al. The fate of Ce in mammalian lung cells probed by STXM, in preparation.