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arXiv · 2405.15277

Inducing ferroelectricity in NH$_4$I and NH$_4$Br via partial replacement of protons by deuterons

Miao Miao Zhao·Lei Meng·Yi Yang Xu·Na Du·Fei Yen
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Abstract

While all of the polymorphs of NH$_4$I and NH$_4$Br are non-polar, a reversible electric polarization is established in the ordered $\gamma$ phases of (NH$_4$)$_{0.73}$(ND$_4$)$_{0.27}$I and (NH$_4$)$_{0.84}$(ND$_4$)$_{0.16}$Br (where D is $^2$H) via $dc$ electric fields. The presence of two groups of orbital magnetic moments appears to be responsible for the asymmetric lattice distortions. Our findings provide an alternative pathway for hydrogen-based materials to potentially add a ferroelectric functionality.

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Miao Miao Zhao, Lei Meng, Yi Yang Xu, Na Du, Fei Yen. 2024-05-24. Inducing ferroelectricity in NH$_4$I and NH$_4$Br via partial replacement of protons by deuterons. https://doi.org/10.1021/acs.jpcc.3c05692

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