Frequent questions and answers

What do you want to know?

What is this service?

Momentum transfer offers a mail-in-service for high-quality and high-throughput synchrotron X-ray powder diffraction measurements. You mail us your samples; we perform the measurements and send you the results.

Use of results?

Our services are suitable for both commercial and academic purposes. Customers own the rights to their results.

How do I get access?

Beamtimes are regularly pre-arranged, meaning that there are no long waiting times for access to measurements. Compared to other methods of paid access, there is no minimum number of samples or shifts that must be purchased by the customer. Additionally, we provide data reduction and validation of results to ensure accuracy, including processing total scattering data to obtain pair distribution functions.

What consultation services are available?

We assist users in various scientific endeavors. We can help determine the optimal measurements needed to solve their scientific problems and provide guidance on data interpretation to help users make sense of their findings. We specialize in performing structure refinement, utilizing methods such as Rietveld or real-space refinement. Furthermore, we have experience in determining various sample properties such as phase contents, impurities, crystallite size, bond lengths, and domain size in disordered materials. Our assistance also extends to aiding with crystal structure determination, including unit cell indexing, simulated annealing, reciprocal- and real-space co-refinements. Lastly, we offer statistical analyses for large datasets, allowing for in-depth exploration of the data.

Which methods do you support?
  • Phase identification
  • Rietveld refinement
  • Phase quantification
  • Unit cell indexing
  • Crystal structure solution via simulated annealing
  • Real space structure refinement
  • Structure mining for local structure analysis
  • Cluster mining for assessment of small nanoparticle distributions
Which payment methods do you accept?

We will provide a quotation on the desired services. Invoices for services can be paid by bank transfer within 30 days. We can also support payment via credit card.

What are benefits of high-energy X-rays?

Sample transparency and minimal issues with absorption or fluorescence for most elements. Thick samples can be used for probing larger sample volumes.

What is the geometry of the experiment?

The experiment is setup in transmission geometry using a 2-dimensional detector. The setup is useful to reduce preferred orientation effects and to obtain symmetric line profiles.

Experiment Specifications

High-resolution X-ray powder diffraction (HR-XRPD)
Detector Distance ~1.5 m
Q-range ~0.16 – 9.1 Å-1
d-spacing 40 – 0.69 Å
Peak resolution ~0.004 Å-1 (determined from first peak integral breadth)
Total scattering (TS)
Detector Distance ~0.3 m
Q-range ~0.32 – 31 Å-1
d-spacing 20 – 0.2 Å
Peak resolution ~0.02 Å-1
Pair distribution function (PDF)
Usable Q-max ≤20 - 30 Å-1 (depending on material)
Real space Δd approx. ≥0.16 – 0.11 Å (determined as π/Qmax)
Maximum distance ≤250 – 300 Å
Small-angle X-ray scattering (SAXS)
Detector Distance ~8.9 m
Q-range ~0.01 – 0.37 Å-1
d-spacing ~630 – 17 Å

Data Quality

Data Quality
Sharp and symmetric instrumental profile

Superior Quality

Using high energy X-rays (75 keV) and highly monochromatic radiation combined with 2D detection results in a sharp and symmetric instrumental profile which is ideal for detecting low-intensity features, decomposing overlapping features, and distinguishing microstructural properties.

Example Data

Nano-crystalline calcium carbonate

X-ray diffration pattern of nano-crystalline calcium carbonate
X-ray powder diffraction pattern
X-ray diffration pattern of nano-crystalline calcium carbonate
Total scattering
X-ray diffration pattern of nano-crystalline calcium carbonate
Pair distribution function

Amorphous organic polymer

X-ray diffration pattern of nano-crystalline calcium carbonate
X-ray powder diffraction pattern
X-ray diffration pattern of nano-crystalline calcium carbonate
Total scattering
X-ray diffration pattern of nano-crystalline calcium carbonate
Pair distribution function