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X-ray Diffractometer (XRD) Malvern Panalytical Empyrean
Characterization of crystalline materials and thin films
The Malvern Panalytical Empyrean X-ray diffractometer enables versatile and non-destructive characterization of the crystalline structure of materials. Conventional powder analysis allows for the identification and quantification of mineral or crystalline phases present, as well as the study of certain structural parameters. The instrument also allows for X-ray reflectometry (XRR) analysis to determine the thickness of thin films greater than approximately 10 nm , and grazing incidence X-ray diffraction (GIXRD) analysis to preferentially characterize phases located near the surface. Finally, in-situ microdiffraction allows for the local study of the structure and crystalline phases of solid materials. These various configurations make the instrument suitable for the analysis of powders, bulk materials, thin films, and numerous natural or synthetic materials.
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Availability and contact
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User Fees
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Sample types
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Technique and applications
X-ray diffraction (XRD) is a technique used to study the organization of matter at the atomic scale. It is mainly used to identify and quantify crystalline phases, but a diffraction pattern also contains information on lattice parameters, crystallographic texture, residual stress, coherent domain size, microstrain and structural disorder. The scattering between and beneath the Bragg peaks can also provide information on the local structure of nanocrystalline, disordered or amorphous materials.
Thanks to a versatile instrumental configuration, the analysis can be adapted to powders, solid fragments, flat surfaces, thin films, nanomaterials and poorly crystalline materials. Depending on the nature of the sample and the information sought, measurements can be carried out in reflection, in transmission, by microdiffraction, by grazing-incidence diffraction (GIXRD) or by X-ray reflectometry (XRR).
1 | X-ray Beam Generation and Conditioning
X-ray Source
In the tube, electrons emitted by a cathode are accelerated at high voltage toward a metal anode. Their deceleration in the field of the nuclei produces a continuum of braking radiation (Bremsstrahlung), while ionization of the anode's inner shells generates characteristic X-ray lines. Most of the electron energy is dissipated as heat, so a cooling circuit stabilizes the source and protects the tube.
The selected wavelength must be known precisely, since it enters directly into the relationship between the diffraction angle and the interplanar spacings. The choice of anode material can also reduce certain unwanted contributions, notably sample fluorescence, and improve the signal-to-background ratio for particular matrices.
Incident Beam Optics
Before reaching the sample, the radiation is conditioned by a combination of slits, mirrors, monochromators, collimators and focusing systems. These components define the beam's divergence, spectral distribution, cross-section and footprint on the sample. Focusing optics are advantageous for powders in parafocusing geometry, while a parallel beam reduces sensitivity to surface displacement and is better suited to films, irregular surfaces and grazing-incidence measurements.
Increasing the flux shortens acquisition time, but greater divergence can broaden the reflections and reduce angular resolution. Conversely, strong collimation improves instrumental resolution at the cost of lower intensity. The configuration is therefore chosen according to the required resolution, the size of the area studied, the crystallinity and the amount of material available.
Technique and applications
Sample types
Powders
For powder analysis, approximately 2 g is generally required. The powder must be homogeneous and sufficiently fine. MicroLab offers grinding with a McCrone; a particle size of less than approximately 10 µm is recommended for Rietveld quantification when the nature of the material allows.
Cohesive solids and layers
Thin sections, polished sections, flat-surface fragments, films, and coatings can be analyzed. Preparation depends on the geometry: microdiffraction, GIXRD, and XRR require precise positioning and a suitable surface.
Maximum dimensions
The instrument can accommodate objects or fragments up to approximately 5 × 5 cm and 10 kg. Mechanical and geometric compatibility must be validated before analysis.
Impact of preparation on quality and repeatability
In powder XRD, the intensities must represent a large number of crystallites oriented in a statistically random manner. Powder that is too coarse produces unstable or non-representative peaks; preferred orientation alters their intensities; and different microabsorption between phases can bias the quantification. Poor packing or vertical displacement of the surface can also shift the peaks. Therefore, grinding, homogenization, and mounting directly influence identification and repeatability. However, excessive grinding should be avoided when it can amorphize, oxidize, or transform the material.
COMPATIBLE SAMPLES
Sample types
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User Fees
MicroLab rates are set according to the type of user, the instrument usage mode and, depending on the service, the analysis time or the number of samples. Some services, particularly sample preparation, may be billed per sample, while instrument use and data processing are generally billed on an hourly or daily basis.
User Categories
Université Laval
This category includes users whose projects are funded, in whole or in part, by Université Laval, regardless of their faculty or affiliated unit. In particular, it includes undergraduate, master’s and doctoral students carrying out work as part of a research project supervised by a Université Laval professor or researcher.
Research / Public Funding
This category includes students, professors, researchers and professionals from other Canadian universities, CEGEPs or research centres, when the work is carried out as part of projects or within institutions funded primarily by public funds. These funds may come, for example, from government or para-governmental organizations, federal or provincial research programs, or other public funding sources.
Industry
This category applies to private companies and to work carried out in an industrial or commercial context.
Usage Modes
When several usage modes are offered for an instrument, rates distinguish between assisted and unassisted use.
Assisted
The instrument is operated by the lead operator or the technical manager, who is responsible for starting the analysis, changing samples when necessary and assisting the user through the various stages of the measurement. This mode is particularly suited to analyses requiring specific instrumental expertise and to occasional users.
Unassisted
After completing appropriate training, users can carry out their own analyses and, when necessary, change samples themselves. Use nevertheless remains under the supervision of the instrument manager. Initial training is billed according to the time required and includes both staff time and instrument use.
Unassisted use is restricted to Université Laval users and depends on the instrument, the type of analysis and the user's level of experience. For the conditions of access to this mode, please contact the manager of the relevant instrument.
Pricing Based on Analysis Duration
For services with hourly and daily rates, billing is based on the total instrument usage time, including the time required to prepare and configure the instrument for the analysis.
For periods under 6 hours, the hourly rate applies. From 6 hours up to 24 hours, a daily flat rate applies. Beyond 24 hours, billing continues in daily increments at the applicable daily rate.
The daily flat rate is particularly advantageous for long analyses: its cost generally corresponds to that of six hours of use, while allowing the instrument to be used for up to 24 hours. It thus prevents costs from rising continuously during extended acquisitions and makes it easier to budget for an analysis session. For example, an analysis lasting 12, 18 or 24 hours is billed at the same daily flat rate rather than as the sum of the individual hours.
Services listed “per sample” are billed according to the number of samples processed, regardless of this hourly/daily structure.