Recording time-resolved structures of complex molecules (such as protein complexes) by femtosecond X-ray pulses is among the important goals of ELI-Beamline's project. However, these techniques are still in the process of being developed and suffer from a high level of damage that is inflicted on a sample. In contrast, time-resolved vibrational spectra can map molecular conformations in a highly non-invasive way. The possibility of running these experiments simultaneously with X-ray experiments would allow for valuable supplementary information to be obtained to cross-validate the conclusions drawn from the X-ray experiments. A crucial advantage of the stimulated Raman probe is the great flexibility it offers in terms of beam delivery, because it is based on pulses in the optical domain.

In time resolved experiment the reaction under study will be first triggered by “actinic pulse”. Subsequently its structural changes will be measured non-invasively by “Raman and transient absorption probe” just few femtoseconds before the arrival of the

Miroslav Kloz, miroslav.kloz@eli-beams.eu