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arXiv · 2202.11992

Magnetic resonance probing of ferroelectricity and magnetism in metal-organic frameworks

Nandita Abhyankar·Sylvain Bertaina·Maylis Orio·Naresh Dalal
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Abstract

We employ electron paramagnetic resonance (EPR) of the spin probe Mn2+ to study the paraelectric ferroelectric transition in DMAMnF and Mn2 doped DMZnF, which are considered to be model metal organic frameworks (MOF) with a Pb free perovskite architecture. In DMAMnF, we study the variation of the Mn2+ EPR line shape and intensity at the X-band (9.4 GHz) and over 80 to 300 K, and we show the absence of magnetoelectric coupling at the ferroelectric transition. At the antiferromagnetic transition in DMMnF, we detect a magnetoelectric coupling caused by weak ferromagnetism in the AFM phase. In DMZnF, the combination of EPR of the Mn2+ probe and DFT show that the crystal field is predominantly determined by the DMA+ cations.

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Nandita Abhyankar, Sylvain Bertaina, Maylis Orio, Naresh Dalal. 2022-02-24. Magnetic resonance probing of ferroelectricity and magnetism in metal-organic frameworks. https://doi.org/10.1080/00150193.2018.1473484

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