Saturation free and time resolved soft X-ray absorption on liquids and colloids /UE52_SGM
The NEXAFS instrument is installed at the soft x-ray beamline UE52_SGM, covering the range of 100 - 1300 eV with an x-ray spot size of approximately 60 µm Polarization can be freely chosen between linear (any orientation) and circular.
The instrument is dedicated to time-resolved and steady-state soft x-ray absorption spectroscopy (XAS/NEXAFS/XANES/EXAFS) in transmission on liquid samples and solids. The liquid sample is continuously refreshed in a flatjet system. The transmitted intensity of synchrotron radiation for ground state NEXAFS is measured with a gallium arsenide photodiode (average diode current is recorded). For static measurements, the full filling pattern of BESSY II is used. For time-resolved measurements, a MHz laser is incoupled to the end station and excites the sample. An avalanche photo diode (APD) is used to separate the "single bunch" in the hybrid filling pattern of BESSY II.
Selected Applications:
- Photo-induced ligand substitution
- Proton transfer - systematic investigations
- Electronic structure changes upon UV excitation
- Detection of excited states by photoabsorption
(a) Schematic top view of the experimental layout for static and time resolved NEXAFS measurements of liquid samples. (b) Thickness variation across a water flatjet based on the transmitted intensity
Methods
NEXAFS, Time-resolved absorption
Remote access
depends on experiment - please discuss with Instrument Scientist