Instrument

Schema

Main components

X-ray source GeniX3D Cu ULD beam delivery system (Xenocs SA, France)
Detector Pilatus-300k hybrid pixel position sensitive detector (Dectris Ltd, Switzerland)
Motor controllers TMCM-351 (2×) and TMCM-6110 (1×) integrated controller & driver for stepper motors (TRINAMIC Motion Control GmbH & Co. KG, Germany)
Vacuum gauge TPG-201 Pirani gauge (Pfeiffer Vacuum GmbH, Germany)
Control software SAXSCtrl: a Python based graphical instrument control and data reduction framework (self developed)

The instrument is of modular construction: all parts are mounted on a single optical rail.

Characteristics

Quantity Value Comments
Attainable q-range 0.019 nm-1 to 30 nm-1 Corresponds to 320 nm to 0.2 nm
Typical beam size at sample 0.7 mm Optimized for 1 mm thick capillaries, possible to increase up to 1 mm
Sample-to-detector distances ~450 mm (short), ~1200 mm (long), ~1500 mm (very long) Other distances can also be used on request
Typical X-ray intensity at sample, short distance 100-150 kcps Expressed in detector count (photon × quantum efficiency) units
Typical X-ray intensity at sample, long distance 50-72 kcps Expressed in detector count (photon × quantum efficiency) units
Vacuum <0.05 mbar Full beam-path vacuum; can be divided in case of vacuum-intolerant sample environments
X-ray wavelength / energy 0.1542 nm / 8048 eV Cu K$\alpha$ radiation
Collimation 3 pin-holes Pin-holes are Pt-Ir electron microscope apertures from 150 µm up to 1250 µm
Sample quantity needed
  • ~ 10µL liquid
  • a few mg of powder
  • ~ 0.5 cm2 of solid plates
 

Sample environment

Sample holders are suspended on a motorized XY stage with 35 mm horizontal and 75 mm vertical stroke length. Sample holders and environments, which can be used include:

  • standard "ladder" for at most 5 self-carrying specimens (solid plates, powder between films)
  • multi-shot "ladder" for at most 14 self-carrying specimens (solid plates, powder between films)
  • aluminum block for at most 5 capillaries of ~1-1.6 mm thickness. Sample temperature can be controlled by water circulation in the block.
  • aluminum block for at most 20 capillaries of ~1-1.6 mm thickness.
  • shear cell with asymmetric sawtooth profile (cannot be used under vacuum)
  • sample holder for 1 capillary, 0.7 T static magnetic field can be applied
  • other sample holders can be constructed or adapted upon request

Calibration samples

Calibration of the scattering angle

The X (scattering angle, momentum transfer) axis of the scattering patterns in the SAXS range is calibrated using the Bragg reflections of a mesoporous SBA15 sample, courtesy of Roland Schmack, MSc. In the WAXS range either tripalmitin or LaB6 is employed.

Intensity calibration

The Y (intensity) axis of the scattering patterns is calibrated using a pre-calibrated glassy carbon specimen, courtesy of Dr. Jan Ilavsky.