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Atypical Magnetic Behavior in the Incommensurate (CH3NH3)[Ni(HCOO)3] Hybrid Perovskite
Breogán Pato-Doldán1, Laura Cañadillas-Delgado2, L Claudia Gómez-Aguirre1
1Department of Chemistry, Faculty of Sciences, Universidade da Coruña, 15071 A Coruña, Spain.
The Journal of Physical Chemistry. C, Nanomaterials and Interfaces
|February 27, 2023
Summary
We investigated the magnetic behavior of a nickel formate perovskite, revealing unusual magnetization reversals. Applied magnetic fields induce a phase transition from incommensurate to collinear magnetic structures.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- (CH3NH3)[M(HCOO)3] compounds, with M=Co(II) or Ni(II), exhibit temperature-induced phase transitions.
- The nickel compound displays magnetic and nuclear incommensurability below its Néel temperature.
Purpose of the Study:
- To deeply investigate the macroscopic magnetic behavior of the nickel compound.
- To understand the origin of atypical magnetic responses in formate perovskites.
- To elucidate the relationship between magnetic properties and the incommensurate structure.
Main Methods:
- Macroscopic magnetic measurements at low temperatures.
- Analysis of magnetization curves and hysteresis loops.
- Theoretical modeling to explain observed magnetic phenomena.
Main Results:
- Observed puzzling magnetization reversal and inability to reach zero magnetization.
- Identified a significant shift in magnetization curves (>1200 Oe) between the first and subsequent loops.
- Ruled out explanations based on unbalanced domain pairs.
Conclusions:
- The atypical magnetic behavior is linked to the material's incommensurate structure.
- Applied magnetic fields induce a phase transition from a magnetically incommensurate to a modulated collinear magnetic structure.
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