Electron beams are often treated as a problem in molecular electron microscopy: powerful enough to reveal structure, but also capable of damaging the very samples under study. A recent paper published in Angewandte Chemie International Edition suggests a different possibility: what if beam damage could be harnessed as beam-enabled chemistry?

In the study, BioPACIFIC MIP faculty member Miguel A. Garcia-Garibay and coauthors Rishika Rai and Krzysztof A. Konieczny show that high-energy electrons can initiate controlled chemical reactions in molecular crystals. Working with crystalline thymine dimers, the researchers found that exposure to an electron beam triggered solid-to-solid splitting reactions, converting the dimers back to thymine-based products through an ionization-induced, single-electron-transfer chain reaction.

The work brings together electron microscopy, electron diffraction, spectroscopy, and crystallography to show how the electron beam can serve as both a probe and a chemical stimulus. Rather than simply degrading the crystal, the beam initiates a reaction that can be tracked and structurally analyzed, including through microcrystal electron diffraction.

The result points to an intriguing shift in how researchers think about beam-sensitive molecular materials. Interactions once viewed primarily as sample damage may also become a way to study, amplify, and direct chemical reactivity inside crystals with exceptional precision.