Inelastic Scattering of X-Rays with Very High Energy Resolution

Inelastic scattering of X-rays with very high energy resolution has finally become possible thanks to a new generation of high-intensity X-ray sources. This development marks the end to the traditional belief that low energy excitations like lattice vibrations cannot be resolved directly with X-rays: Inelastic scattering experiments allow to observe directly the small energy shifts of the photons. Studies of lattice vibrations, of excitations in molecular crystals, of collective excitations...