MLZ is a cooperation between:
> Technische Universität München
> Helmholtz-Zentrum Geesthacht
> Forschungszentrum Jülich
MLZ is a member of:
> LENS
> ERF-AISBL
MLZ on social media:
MLZ (eng)
Lichtenbergstr.1
85748 Garching
HEiDi
Single crystal diffractometer on hot source
The single crystal diffractometer HEiDi is designed for detailed studies on structural and magnetic properties of single crystals using hot unpolarised neutrons and Bragg’s Law:
2 dhkl sin (Θ) = λ
(typically 0.55 Å < l < 1.2 Å).
Because of the large variety of short wavelengths and resolutions, HEiDi is suitable for studies on a lot of crystalline compounds – many of them of potential interest for energy or data storage technologies – like:
- HT superconductors (e.g. cuprates, FeAs-pnictides)
- Multiferroics (e.g. manganates) and other complex ferro- and antiferromagnetic compounds (e.g. olivines)
- Ionic conductors (e.g. nickelates)
- Ferroelectrics (e.g. KDP family)
- Mixed crystals (e.g. AsSe compounds)
- Highly absorbing compounds (e.g. with Gd, Sm, Eu, Dy)
- Frustrated magnetic materials (e.g. pyrochlores)
- Structure analysis
- Hydrogen bonds
- Static and dynamic disorder
- Harmonic and anharmonic mean square displacements
- Twinning
- Magnetic structure and order
- Structural and magnetic phase transitions
- Incommensurate structures
- Studies of atomic positions and bond distances in compounds with heavy and light elements or elements of similar electron shells
- Temperature dependent studies for determination of phase transitions
- Studies of order – disorder phase transitions, e.g. H bonds by determination of anisotropic mean square displacements using large Q range up to sin(Θ)/λ > 1
- Structure determination of compounds with highly absorbing elements (Gd, Sm, Cd, Dy) with short wavelengths
- Studies on magnetic phase transitions and T dependencies (ferri, ferro and antiferro magnets, multiferroics)
- Studies on HT superconductors (e.g. cuprates, FeAs pnictides)
- Sample characterisation by profile analysis
- Determination of sample orientation, e.g. for preparation of experiments on three axes instruments
- Presentation of fundamentals of crystallography and structure analysis for education
- Closed cycle cryostat (2 K – RT)
- Mirror furnace (RT – 1500 K)
- Micro furnace (RT – 500 K)
- Uniaxial pressure cell (from PUMA)
Beam-tube
- SR9B (hot source)
- Flux at sample 1.4·107 cm-2s-1
(λ ≈ 1.17 Å) - Gain by hot source × 10 (λ ≈ 0.6 Å)
Wavelength
| 2ΘM | Ge(311) | Cu(220) | Ge(422) | Cu(420) |
| 20° | 0.503 | 0.443 | 0.408 | 0.280 |
| 40° | 1.168 | 0.870 | 0.793 | 0.552 |
| 50° | 1.443 | 1.079 | 0.993 | 0.680 |
Q-range
| 2ΘM | Ge(311) | Cu(220) | Ge(422) | Cu(420) |
| 20° | 1.46 | 1.95 | 2.12 | 3.09 |
| 40° | 0.74 | 0.99 | 1.09 | 1.57 |
| 50° | 0.60 | 0.80 | 0.87 | 1.27 |
- Single detector optimized for small wavelengths (sensitivity >90% at
0.3 Å) - Analyzer PG(002); optional for studies of purely elastic scattering and background suppression
- Neutron filters for suppression of λ/2- or λ/3-contamination of the monochromatized beam
Instrument Scientists
Dr. Martin Meven
Phone: +49 (0)89 289-14727
E-Mail: martin.meven@frm2.tum.de
Dr. Rajesh Dutta
Phone: +49 (0)89 289-54811
E-Mail: rajesh.dutta@frm2.tum.de
Dr. Hao Deng
Phone: +49 (0)89 289-54725
E-Mail: hao.deng@frm2.tum.de
HEIDI
Phone: +49 (0)89 289-14828
Operated by
Publications
Find the latest publications regarding HEiDi in our publication database iMPULSE:
Citation of the instrument
Heinz Maier-Leibnitz Zentrum. (2015). HEiDi: Single crystal diffractometer at hot source. Journal of large-scale research facilities, 1, A7. http://dx.doi.org/10.17815/jlsrf-1-20
For citation please always include the DOI.
Gallery
MLZ is a cooperation between:
> Technische Universität München> Helmholtz-Zentrum Geesthacht> Forschungszentrum Jülich
MLZ is a member of:
> LENS> ERF-AISBL
MLZ on social media: