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Microscopic Insights on the Multiferroic Perovskite-Like [CH3 NH3 ][Co(COOH)3 ] Compound
Lidia Mazzuca1, Laura Cañadillas-Delgado1,2, Oscar Fabelo1
1Diffraction Group, Institut Laue Langevin, 71 Avenue des Martyrs, CS 20156, 38042, Grenoble Cedex 9, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|September 1, 2017
Summary
This study characterizes the [CH3NH3][Co(COOH)3] metal-organic compound, revealing a structural phase transition around 90 K that triggers an antiferroelectric-like phase and magnetic ordering below 15 K.
Area of Science:
- Materials Science
- Crystallography
- Solid State Physics
Background:
- Metal-organic compounds with perovskite-like structures are of interest for their unique physical properties.
- Understanding phase transitions and magnetic ordering is crucial for developing new functional materials.
Purpose of the Study:
- To characterize the crystal structure, phase transitions, magnetic structure, and dielectric properties of [CH3NH3][Co(COOH)3].
- To investigate the relationship between structural and dielectric phase transitions.
Main Methods:
- Variable-temperature single-crystal and powder neutron and X-ray diffraction.
- Relative permittivity measurements.
Main Results:
- A paraelectric to antiferroelectric-like phase transition was observed around 90 K, triggered by a structural change from Pnma to P21/n space group.
- Neutron diffraction revealed a non-collinear antiferromagnetic structure with a weak ferromagnetic component below 15 K, attributed to Co(II) ion anisotropy.
Conclusions:
- The [CH3NH3][Co(COOH)3] compound exhibits coupled structural, dielectric, and magnetic phase transitions.
- The observed properties are influenced by framework distortions and counterion arrangements, along with single-ion anisotropy.
Keywords:
magnetic structuremetal-organic compoundsmultiferroic materialsneutron diffractionphase transitionsMore Related Videos
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