X-ray emission spectroscopy is a well established and powerful tool for investigating the occupied electronic states of atomic or molecular specimen. It allows an energy selective excitation of a sample and a site selective probing. The method is based on electron excitation via X-rays and subsequent analysis of the resulting fluorescence in terms of photon energy using dispersion gratings.
The LiXEdrom setup, which is under construction at the moment, will combine the X-ray emission spectroscopy with a high pressure liquid jet, allowing the investigation of samples in liquid phase. Up to now XES measurements on liquids have been performed only in drop-behind-membrane configuration, where sample damage by radiation could not be avoided. The novel combination of XES with a high pressure liquid jet opens the door for a broad range of applications, such as the investigation of pure water, ions in solution, as well as complex biochemical systems e.g. proteins in their natural environment.