Developing femtosecond resolution methods for directly observing structural dynamics is
critical to understanding complex photochemical reaction mechanisms in solution. We have
used two recent developments, ultrafast mega-electron-volt electron sources and vacuum
compatible sub-micron thick liquid sheet jets, to enable liquid-phase ultrafast electron
diffraction (LUED). We have demonstrated the viability of LUED by investigating the
photodissociation of tri-iodide initiated with a 400 nm laser pulse. This has enabled the …