SPHERICAL GRATING MONOCHROMATOR (SGM) BEAMLINE

SGM - XAS

Ambient Pressure X-ray Absorption Spectroscopy (XAS) Endstation

  Normal Operations

Beamline_Side_View_CAD_XAS

Chamber

  • Translatable endstation with atmospheric control
  • Motorized leak valve and gas manifold
  • KB mirror for refocusing the beam
  • KB mirror box separated from chamber by a silicon nitride window
  • Six axis sample stage (hexapod) with 1 um resolution

Detectors

  • Four silicon drift detector array
  • Drain current from sample
  • Drain current from Au coated mesh before the KB mirrors used to measure the incident flux (I0)
  • Residual gas analyzer
  • Digital optical microscope
  • Optical spectrometer

Software

  • We are using the program SPEC for instrument control and data acquisition on the XAS endstation.
  • User data acquisition takes place in a Jupyter notebook environment, controlling SPEC in server mode.
  • Consult the SGM SPEC Manual for controlling the beamline and collecting data on the XAS endstation.

Sample Information & Accessories

Samples

Solid and liquid samples are routinely measured on the XAS endstation. Measurement of gas samples is possible but is not routinely done.

Sample holders are highly customizable and can be adapted for mounting almost any type of sample. Consult with the beamline staff for an alternative mounting strategy.

The beam spot size is routinely 50 um x 50 um. Consult with the beamline staff if a larger or smaller beam spot is required.

Detailed information can be found in the Data Collection and Analysis section under Sample Collection and Preparation.SGM Beamline

Techniques

  • X-ray fluorescence mapping
  • X-ray absorption spectroscopy
    • Total electron yield (TEY)
    • Partial fluorescence yield (PFY)
  • X-ray excited optical luminescence (XEOL)