AVS 53rd International Symposium
    Ultra-Bright Light Sources Topical Conference Wednesday Sessions
       Session UB-WeM

Paper UB-WeM13
In-Situ Electronic Structure Study of Chemical Reactions with Photon-In/Photon-Out Soft-X-Ray Spectroscopy

Wednesday, November 15, 2006, 12:00 pm, Room 2001

Session: Ultra-Bright Light Sources Topical Conference
Presenter: J.-H. Guo, Lawrence Berkeley National Laboratory
Correspondent: Click to Email
The electronic structure ultimately determines the properties of matter. Photon-in/photon-out soft-x-ray spectroscopy has been the subject to a revived interest owing to the new generation synchrotron facilities and high performance beamline and instruments. Soft-x-ray absorption spectroscopy (XAS) probes the local unoccupied electronic structure, soft-x-ray emission spectroscopy (XES) probes the local occupied electronic structure, and resonant inelastic soft-x-ray scattering (RIXS) probes the intrinsic low-energy excitations, such as charge transfer, proton energy transfer etc. Photon-in/photon-out soft X-ray spectroscopy is essentially bulk sensitive, since the attenuation length of photons in this energy range is typically hundreds of nanometers in solid matter. The penetration depth offers a few experimental opportunities not present in electron based spectroscopies. Here we take advantage of the large photon attenuation length to perform the first X-ray emission study of liquid water and solutions. The liquid cell has a window to attain compatibility with UHV conditions of the spectrometer and beamline, The synchrotron radiation enters the liquid cell through a 100 nm thick silicon nitride window and the emitted X-rays exit through the same window. This allows in particular liquid/solid interfaces to be studied. A number of examples, including some recent experimental findings, then illustrate the potential of XAS and XES applications in materials sciences.