Related Experiment Video
Updated: May 22, 2025

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Disorder- and magnetism-driven structural changes in Sm2Mn1-xGa6-yGey
Roman A Khalaniya1, Andrei V Mironov1, Aleksandr Kulchu1
1Department of Chemistry, Lomonosov Moscow State University, GSP-1, 1-3 Leninskiye Gory, Moscow, 119991, Russian Federation.
Abstract:
The crystal structure of Sm2Mn1-xGa6-yGey has been studied over a wide temperature range (180-430 K) using high-resolution single-crystal X-ray diffraction experiments. The compound belongs to a large family of filled AuCu3-type gallides and features a cubic F-centred structure created by alternating empty and Mn-filled p-element octahedra in a 3D-chequerboard pattern. Temperature dependence of the unit-cell volume reveals several narrow regions of negative thermal expansion (NTE) near the magnetic phase transitions. The structure analysis reveals that the appearance of NTE regions stems from the changes in the atomic coordinates and displacement upon the magnetic transitions. Between 375 and 400 K, an additional and purely structural transformation, is observed which is caused by the structure relaxation as a result of the structural defects.
More Related Videos
09:06Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Related Concept Videos
Atomic Nuclei: Nuclear Relaxation Processes
Ferromagnetism
Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
Diamagnetism
Diamagnetism was discovered by Anton Brugmans in 1778 when he observed that bismuth gets repelled by magnetic fields, thus theorizing that diamagnets get repelled by magnets....
Paramagnetism
Atomic Nuclei: Magnetic Resonance