Inelastic X-ray scattering: a new technique for studying dynamics in liquids

Abstract

Inelastic X-ray scattering with an energy resolution of the order of meV is a young method that is proving to be an excellent tool for investigating collective excitations in condensed matter. The high energy resolution can be achieved by extreme backreflection (Bragg angle close to 90 degrees ) from perfect crystals. This technique is used on the instrument INELAX for inelastic scattering experiments at DORIS, DESY Hamburg. Energy transfers from a few meV up to 5 eV for any wavevector between 0.3 AA^-1 and 14 AA^-1 are accessible. One of the successful applications of this method is the investigation of the dynamical structure factor of liquids. Results on liquid lithium are presented and compared with neutron data and molecular dynamics.