Ultrafast X-ray Induced Dynamics in Small Molecules

XFELs provide highly intense, femtosecond X-ray pulses that are ideal for the study of photoionization dynamics in atoms and molecules. In this presentation, I will two main bodies of work: first, the commissioning of a Cold Target Recoil Ion Momentum Spectroscopy (COLTRIMS) experimental setup at the Maloja endstation of SwissFEL; and second, the investigation of ultrafast dynamics in ethanol following core ionization above the oxygen K-edge, with focus on the intramolecular hydrogen transfer and roaming mechanisms. Upon ionization in the O K-edge region of ethanol, the dynamics of the H+, H2+ and H3+ ions that were formed were studied using time-resolved ion time-of-flight spectroscopy, employing an X-ray pump/near-infrared (NIR) laser probe scheme. The results reveal dynamics showing the effect of core ionization in populating excited cationic states, resulting in phenomena such as a faster roaming time and an increase in kinetic energy of the ejected fragment ions.