GoKawiilPAL-XFEL study maps ultrafast atomic motions during azobenzene light-switching
Researchers used time-resolved X-ray liquidography at South Korea's PAL-XFEL free-electron laser facility to track the structural changes azobenzene molecules undergo when switched from trans to cis form by a laser pulse. The experiment combined a 400 nm pump laser with X-ray probe pulses to capture molecular motion with a measured time resolution of about 169 femtoseconds, using a single-pass capillary jet of the dissolved sample rather than a recirculated solution.