Rapid single crystal structure analysis using high-flux synchrotron radiation of SPring-8

We realized the milliseconds rapid diffraction measurement using the high-flux synchrotron radiation (SR) of SPring-8 and a high frame rate photon counting detector in BL40XU beamline. We carried out single crystal X-ray diffraction measurements at high rotation speeds up to 80,000 rpm (0.75 ms/rotation) in order to evaluate the limitations of the measurement time and the accuracy of molecular structure. Using a high-speed spindle motor for sample rotation, we successfully analyzed the structure of cytidine (C₉H₁₃N₃O₅) from a dataset of a 60 ms measurement time at a 1,000 rpm sample rotation. However, although weak diffraction spots were clearly observed, the crystal structure could not be solved at an 80,000 rpm sample rotation. These results show that it is possible to observe the crystal structure or lattice parameter changes during one-shot irreversible chemical reactions using the millisecond rapid diffraction measurement.