Neutron single-crystal diffractometer HEiDi
The single-crystal diffractometer HEiDi uses unpolarized neutrons of different wavelengths in a range between 1.4 and 0.5 Å. Due to the availability of short-wave (“hot”) neutrons at the hot source of the FRM II (beam channel SR-9a / Sr-9b) of the Heinz Maier-Leibnitz Zentrum (MLZ) in Garching near Munich, it is suitable for high-resolution crystal structure analyzes in a large Q area. In addition, investigations are possible in a wide temperature range between approx. 2,5 K to 1300 K and, most recently, also with pressure cells up to approx. 5 GPa. Typical questions concern the precise determination of hydrogen positions and bonds, e. g. in molecules and framework structures or other light elements, e. g. in ion conductors, often in connection with the investigation of anharmonic thermal oscillations, defect structures, static and dynamic disorder as well as the determination of magnetic order states.
HEiDi has been in user operation since 2005 and has been operated together with JCNS since 2011.
| Technical features |
Sample temperatures: 2,5 K < T < 1300 K |
| Application | High resolution analysis of chemical and magnetic structures, hydrogen bonds, mixed crystals, static and dynamic disorder, harmonic and anharmonic mean square displacements, structural and magnetic phase transitions, twinning, modulated and incommensurate structures |
Further information for HEiDi can be found on the MLZ website.
Team:
Dr. Martin Meven (1st local contact)
N. N. (2nd local contact)
Wolfgang Luberstetter (project engineer)
Publications:
Meven, Martin; Sazonov, Andrew: HEiDi: Single crystal diffractometer at hot source. Journal of large-scale research facilities 1 (2015) A7, DOI: 10.17815/jlsrf-1-20.
Meven, Martin; Hutanu, Vladimir; Heger, Gernot: HEiDi: Single crystal diffractometer at the hot source of the FRM II. Neutron News 18(2) (2007) 19-21, DOI: 10.1080/10448630701328406.
Actual scientific topics in connection with the user operation:
| Magnetic ordering in Eu(Fe1-xCox)2As2 | Garnet-type solid state electrolyte Li6La3ZrTaO12 |
Funding:
Operation of the Neutron Diffractometers HEIDI and POLI at the Heinz Maier-Leibnitz Zentrum in Garching
Jülich Centre for Neutron Science/Forschungszentrum Jülich
Jülich Aachen Research Alliance
Development and optimization of the high-pressure devices for polarised and non-polarised neutron diffraction and spectroscopy on the beamlines HEiDi, POLI, MIRA, and DNS at the Heinz Maier-Leibnitz Zentrum, see project
Exploring oxygen diffusion mechanisms in Pr2NiO4+δ under in-situ conditions by neutron scattering: interplay between structure and lattice dynamics, see project