A team of physicists has successfully captured the real-time break-up of C60 fullerenes using advanced X-ray imaging techniques, marking a significant breakthrough in the understanding of molecular dynamics under intense laser fields. The experiment, carried out at the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory, involved a collaborative effort from multiple institutions, including the Max Planck Institute for Nuclear Physics (MPIK) in Heidelberg and the Max Planck Institute for the Physics of Complex Systems (MPI-PKS) in Dresden.
This innovative research, published on November 21, 2025, in the journal Science Advances, utilized ultrashort and intense X-ray pulses from accelerator-based free electron lasers (FELs). This technology allows scientists to observe how molecules like C60, known for their unique football shape, respond to laser-induced forces in real time.
Understanding Molecular Dynamics
The study focuses on the complexities of many-body dynamics in polyatomic molecules, which are essential for manipulating chemical reactions using light. By analyzing the X-ray diffraction pattern resulting from the interaction of a strong infrared (IR) laser pulse with the C60 molecules, researchers were able to extract critical parameters regarding the molecule’s structure. These include the average radius (R) of the molecule and the Guinier amplitude (A), the latter indicating the strength of the X-ray scattering signal.
The experiments were conducted across various laser intensity levels, from 1×10^14 W/cm² to 8×10^14 W/cm². The variations in R and A provided insights into the molecular expansion, deformation, and fragmentation processes. At lower intensities, the C60 molecules expanded before fragmenting, while at higher intensities, rapid expansion occurred alongside a significant reduction in the Guinier amplitude, indicating that most outer valence electrons had been stripped away.
Future Implications for Chemical Reactions
The findings suggest that while the model calculations performed at MPI-PKS aligned with some experimental outcomes, there was a notable discrepancy, particularly in the predicted oscillatory behavior of the molecule. To address this, the researchers proposed incorporating an additional ultrafast heating mechanism to better simulate the atomic positions within the molecule. This adjustment led to improved agreement between the theoretical and experimental results.
Understanding the multi-electron dynamics driven by intense laser fields remains a complex challenge. The current research emphasizes that X-ray movies of structural dynamics, such as those produced in this study, serve as valuable tools for exploring fundamental quantum processes in increasingly complex molecular systems.
This groundbreaking work not only enhances our comprehension of molecular interactions but also illuminates potential pathways for controlling chemical reactions through laser fields, paving the way for advancements in fields ranging from materials science to pharmaceuticals.
The collaborative effort involved researchers from the Max Born Institute (MBI) in Berlin, as well as institutions from Switzerland, the United States, and Japan, highlighting the global significance of this research. As scientists continue to push the boundaries of high-intensity laser applications, the implications of this study are likely to resonate across various scientific disciplines, promoting new discoveries and technologies.
