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 |
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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.