Abstract
The use of femtosecond pulses produced by x-ray free-electron-laser (XFEL) sources to image the structures of biomolecules involves a competition between the elastic scattering of photons to form a diffraction pattern and the damage initiated by inelastic collisions with the target. Since the electron density of the biomolecule changes rapidly throughout its interaction with a femtosecond XFEL pulse, the diffraction process measured in “diffract and destroy” experiments is, at best, partially coherent. It has been established that a detailed knowledge of these electrodynamical processes may be used to ameliorate the effects of damage in diffractive imaging experiments. It is shown here that, subject to conventional assumptions about the nature of the interactions, it is possible to characterize the extent of electronic damage in biomolecular imaging experiments using XFELs and to use this information transferably across similar systems. We develop a physical model of the interaction of a coherent x-ray pulse with a molecular system that describes the dynamical electronic response of the molecule. The resulting insights open a way forward for the measurement of atomic processes in such systems.
- Received 17 August 2012
DOI:https://doi.org/10.1103/PhysRevA.87.053407
©2013 American Physical Society