Sensitivity of time-resolved diffraction data to changes in internuclear distances and atomic positions

Time-resolved x-ray liquidography (TRXL) is a powerful technique to study molecular structural dynamics in the solution phase. Typically, a TRXL experiment is conducted during limited beamtime at a beamline of a synchrotron or an x-ray free-electron laser, demanding a proper design and careful planning. In this regard, the optimal q range needs to be determined to find the optimal x-ray energy and sample-to-detector distance. For such purpose, here, we present effective ways to quantify the sensitivity of the TRXL data as a function of q to various factors such as the atomic positions, internuclear distances, solvent cage, and bulk solvent. The developed approaches are also applicable to other types of time-resolved diffraction, such as ultrafast electron diffraction.