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X-RAY DIFFRACTION LABORATORY |
| Short description of the laboratory activity | TOP |
X-Ray Diffraction Laboratory was founded in 2008 within the Condensed Matter Department, whose main activity is the synthesis of advanced crystalline materials. As a necessity imposed by the need to determine the composition, crystallinity degree and structure of the achieved materials, the Laboratory possesses a very performant last generation equipment, namely X’Pert PRO MPD. Assisted by a series of optical components and holders for different types of samples, X’Pert PRO MPD can be configured in order to achieve the desired diffraction method, up to the studied material. Even if recently founded, the laboratory is on the course to be certified, aiming to develop as much as possible the equipment’s potential by training the personnel, by attracting new partnerships and services, and nevertheless by promoting and involving the undergraduate and postgraduate students in the Laboratory’s activity.
| Techniques for analysis and characterization used within the laboratory. X-Ray diffraction | TOP |
Manufacturer: PANalytical, Olanda |
Technical characteristics:
Accessories:
Software:
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Applications:
- analysis and identification of crystalline structure of materials as powders at ambient temperature
- analysis and identification of crystalline structure of powder materials as a function of temperature (-193ºC up to 2000ºC) and gas composition (air, inert gases, oxygen) (on the course to be developed)
- study of the crystalline structure, of density and thickness of thin layers (on the course to be developed)
- study of the deformations of materials by stress analysis (on the course to be developed)
- the study of crystallites orientation inside a material (mostly for metals and ceramics) by texture analyses (on the course to be developed)
- analysis and identification of the crystalline structure of organic compounds using x-ray transmission (on the course to be developed)
- analysis and identification of crystalline nanometer materials structure
Characteristics of the analyzed samples:
- Semi or crystalline materials as powders or monocrystals
- Thin layers, layers on substrates, metals (on the course to be developed)
| Results: | TOP |
Diffraction spectra for a polycrystalline material of Si0.97Sn0.03O2 type
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Diffraction spectra with fluorescence, with and without diffracted side monochromator for PIXcel detector, feritte sample.
| Short description of the technique: |
X ray diffraction is a non-destructive technique which allows the achievement of precise information regarding the chemical composition and crystalline structure of natural and synthesis materials. The basic characteristic of this method is the study of the connection between x ray scattering and spatial arrangement of the atoms.
If we send an x ray beam upon an atoms ensemble, their electronic clouds will interact with the incident wave, scattering it. When radiation is scattered on a given object, both elastic scattering, which takes place without losses of energy and without modification of the wave length λ is produced, and also non-elastic scattering appears. The main role is played by the elastic scattering and this is because it determines the diffraction figure, whose analysis allows establishing the place of the atoms inside the material. Diffraction on crystals can be interpreted as a “reflection” of the x rays on the crystalline network planes. The “reflection” is produced only when the waves, scattered by the parallel planes, are in phase and amplify each by each other, meaning if the half way achieved by scattering and gathered from the neighboring planes is equal to an integer n of wavelengths λ:
This represents the Wulf-Bragg formula, which makes the connection between the propagation direction of the scattered beams (θ angles) and the distances between the dhkl planes in the network, n being the reflexion order. If this condition is not achieved, then due to the existence in the crystal of a high number of planes, the phase differences which make the reflexion appear on them, will lead to the total extinguish of the beams scattered under any other angles, different from that given by the Wulf-Bragg condition.
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| Quartz diffraction spectra | Atoms spatial arrangement |
| Services: | TOP |
- Study of the crystalline structure by x ray diffraction;
- Primary training in X ray diffraction.
| Contact: | TOP |
| Head of Laboratory | Person responsible for the device: |
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0256494413, int. 108 |
0752197756 |