X-Ray Diffraction (draft)

  • What we do

    From the local to global average structure, we support structure investigations of materials from crystalline nanomaterials to macroscopic single crystals at ambient and non-ambient conditions.

  • What we do

    From the local to global average structure, we support structure investigations of materials from crystalline nanomaterials to macroscopic single crystals at ambient and non-ambient conditions.

X-ray Diffraction

X-rays are scattered by the electronic shells of the atoms. Regular periodic arrangement of the atoms leads to sharp diffraction peaks described by the Bragg-equation, all deviations from the periodicity gives rise to the so-called diffuse scattering. Bragg-scattering can be evaluated by Rietveld-refinements. With adapted measurement techniques the sample’s diffuse scattering can be evaluated as well (Total-Scattering).

What kind of result do I get?

The measurement result is a diffractogram, which is used to determine the phase composition of the sample. In the case of well crystalline samples, Rietveld refinements use the Bragg scattering information to refine an average structure model. Total scattering data can be evaluated using either models based on statistical ensembles of crystallites (genetic-algorithms) or large super-cells of an average structure model in which disorder is included on every atomic position using Reverse-Monte-Carlo methods.

Principal Investigator

Prof. Dr. Thorsten M. Gesing

Application Scientist

Dr. Lars Robben
X-ray diffraction and SEM lab head
Radiation protection office @ CKfS
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Our key instruments

Stoe Stadi MP
Powder X-ray diffractometer

  • Transmission and reflection geometry with Mo radiation
  • Measurements from 10 K to 1800 K
  • Total-scattering pre-measurements for applications at large-scale research facilities
mehr

Bruker D8 Venture
4-circle diffractometer

  • Monochromatic Mo Kalpha radiation
  • 2D detector
  • Measurements from 170 K to 1270 K
mehr

Bruker D8 Advance
Cu and Mo X-ray powder diffractometer

  • Bragg-Brentano and transmission geometry
  • Measurements from 100 K to 1500 K
mehr

More available instruments

Current instrumentation belonging to MAPEX-CF can be found in the Instrument Database of the MAPEX Center for Materials and Processes.

A click on the logo will lead you to the database.

Research Highlights

Mechanochemical synthesis of (Mg1−xFe x )2SiO4 olivine phases relevant to Martian regolith: structural and spectroscopic characterizations article picture
X-Ray Diffraction| Spectroscopy|

Mechanochemical synthesis of (Mg₁₋ₓFeₓ)₂SiO₄ olivine phases relevant to Martian regolith: structural and spectroscopic characterizations

Izzuddin Jundullah Hanafi, M. Mangir Murshed, Lars Robben, Thorsten M. Gesing

Zeitschrift für Kristallographie - Crystalline Materials (2024)

https://doi.org/10.1515/zkri-2024-0078

To fabricate metals from the base materials for future Mars exploration, synthesis of representative olivine phases…


Broadening the Realm of Nanoporous Gold Catalysts: Preparation and Properties When Emanating from AuCu as Parent Alloy article picture
X-Ray Diffraction| Spectroscopy| Electron Microscopy|

Broadening the Realm of Nanoporous Gold Catalysts: Preparation and Properties When Emanating from AuCu as Parent Alloy

Jorge Adrian Tapia Burgos, Christoph Mahr, Alex Ricardo Silva Olaya, Lars Robben, Marco Schowalter, Thorsten GesingAndreas Rosenauer, Gunther Wittstock, Arne Wittstock, Marcus Bäumer

ChemCatChem (2024): e202400280

https://doi.org/10.1002/cctc.202400280

Nanoporous gold (npAu) attracted…


Synthesis of a stable crystalline nitrene article pic
X-Ray Diffraction|

Synthesis of a stable crystalline nitrene

Marvin Janssen, Thomas Frederichs, Marian Olaru, Enno Lork, Emanuel Hupf, Jens Beckmann 

Science 385(6706) (2024): 318-321

DOI: 10.1126/science.adp4963

Nitrenes are a highly reactive, yet fundamental, compound class. They possess a monovalent nitrogen atom and usually a short life span, typically…


Aktualisiert von: MAPEX