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Updated: Jun 3, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Structural and magnetic modulations in CaCu(x)Mn(7 - x)O(12).
W Sławiński1, R Przeniosło, I Sosnowska
1Institute of Experimental Physics, Faculty of Physics, University of Warsaw, Hoża 69, PL-00 681 Warsaw, Poland.
Summary
Neutron diffraction reveals atomic and magnetic modulations in CaCu(x)Mn(7-x)O(12) compounds. A key finding is the confirmed relationship between atomic and magnetic modulation lengths, L(m) = 2L(p), below the Néel temperature.
Area of Science:
- Materials Science
- Solid State Physics
- Crystallography
Background:
- CaCu(x)Mn(7-x)O(12) exhibits complex magnetic and structural properties.
- Previous synchrotron X-ray diffraction suggested atomic position modulations.
Purpose of the Study:
- To investigate low-temperature atomic and magnetic modulations in CaCu(x)Mn(7-x)O(12) (x = 0.0, 0.1, 0.23).
- To confirm and extend previous findings on atomic modulations.
- To elucidate the relationship between atomic and magnetic structures.
Main Methods:
- Neutron powder diffraction at low temperatures.
- Analysis of propagation vectors and modulation lengths.
Main Results:
- Atomic position modulations and magnetic moment modulations were observed, both propagating along the c-axis.
- Neutron diffraction confirmed the quantitative model for atomic modulations in CaCu(x)Mn(7-x)O(12) (x = 0.0, 0.1).
- The relationship L(m) = 2L(p) between magnetic and atomic modulation lengths was confirmed between 50 K and T(N).
- Magnetic phase transitions near 50 K were observed for x = 0.1 and 0.23, with significant changes in magnetic modulation and coherence lengths.
Conclusions:
- Neutron diffraction provides crucial insights into the coupled atomic and magnetic structures of CaCu(x)Mn(7-x)O(12).
- The findings validate and extend previous structural models.
- The study highlights the complex magnetic behavior and phase transitions in these materials.
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