X-SPEC is a high-flux beamline for electron and soft & hard x-ray spectroscopy of materials relevant for energy applications, covering a wide energy range from 70 eV to 15 keV. In collaboration with our partners at KIT’s Institute for Chemical Technology and Polymer Chemistry (ITCP), X-SPEC operates two experimental stations which offer x-ray absorption spectroscopy (XAS), extended x-ray absorption fine structure (EXAFS), photoelectron spectroscopy with soft and hard x-rays (PES/HAXPES), as well as x-ray emission spectroscopy (XES) and resonant inelastic x-ray scattering (RIXS).
At the first experimental station, samples can be investigated under ultra-high vacuum (UHV) conditions, while the second experimental station is optimized for in situ and operando studies.
The beamline is currently in a commissioning/early operation stage.
The schematic design of the X-SPEC beamline is shown below. The top shows a bird’s-eye view of the actual design drawing, while the bottom shows a schematic of the most important components of the beamline. From left to right: undulator source with two magnetic structures (U28 and U50), slit system (S1), hard X-ray monochromator (DCM), soft X-ray monochromator (FVLS-PGM), hard X-ray mirror M1, soft X-ray monochromator exit slit, hard X-ray mirror M2, and soft X-ray mirrors M3, M4, M5 and M6. The positions of the two endstations in the schematic are depicted with cloudy orange spheres. In the bird’seye view, the two beam shutters (BS1 and BS2) and the two diagnostic modules (DMA and DMB) are labeled as well. The soft X-ray beam path is shown in red, the hard X-ray beam path in blue.
One of the central design goals of X-SPEC is to combine the strengths of HAXPES and soft XAS/XES/RIXS in one instrument, where these techniques can be used on the same spot of one sample, i.e. under exactly the same preparation conditions, while keeping the beamline layout as simple as possible, thus allowing for quick and easy switching between soft and hard X-rays, and covering photon energies as high as 15 keV without any gap between the `soft' and `hard' energy ranges.