Anomalous Small Angle X-Ray Scattering (ASAXS)

The ASAXS facility at NSF’s ChemMatCARS focuses on element specific structural study of soft matter systems such as polyelectrolytes, colloids, polymers, macro-ions in solutions, and nanomaterials at the length scales from a few nanometer to hundreds of nanometer. NSF’s ChemMatCARS has developed a set of easy to use analysis tools which enable the users to extract quantitative spatial distribution of specific elements (with atomic number Z> 25) within their samples from ASAXS measurements.

Current Capabilities

  • Energy-Range: 6-70 keV (which provides sensitivity to elements with atomic number Z>25)
  • Two fixed sample-to-detector distances available pertaining to Q-Range:
    • 0.003 – 0.2 Å-1 (Sample-to-detector distance: 3.7m at 12keV)
    • 0.01– 0.8 Å-1 (Sample-to-detector distance: 0.57m at 12keV)
  • Area Detectors: Pilatus3 X 300K (6-30keV), Pilatus3 X CdTe 1M (20-70keV)
  • Auto retractable photodiode system very close to the sample for accurate sample transmission measurements
  • Energy Dispersive Detector: Vortex®-60EX silicon drift X-ray Fluorescence detector for energy calibration
  • Sample Environments: Ambient condition sample holders for solid and liquid samples, computer controlled flow cell setup for liquid samples
  • Software: Python based full suite of software package with GUIs available for automated data collection, reduction and analysis of ASAXS data