Atomistic Simulations of In-Situ X-Ray Scattering Probed Material Dynamics

Materials dynamics experiments are challenging in part due to the short time scale and the difficulty of probing the material state in situ. Surface velocity and recovery experiments have been most valuable historically. With the advent of intense x-ray sources paired with laser drives, x-ray diffraction and other x-ray scattering techniques are proving to be tremendously valuable as well, offering new insights into the microscopic behavior of the materials. They probe lattice-level material response and are matched well to atomistic simulation. Simulation techniques like molecular dynamics (MD) can generate synthetic signals to be compared directly to x-ray scattering data and provide important guidance to interpret the signals. Here we discuss several cases. We primarily focus on the use of MD simulation to inform Extended X-ray Absorption Fine Structure (EXAFS) experiments that probe metal temperature in situ during dynamic loading. We also briefly discuss MD results for inelastic x-ray scattering, x-ray radiography and other x-ray probes.