Electric Polarization and Magnetic Properties of (NH$_4$)$_{1-x}$K$_x$I (x = 0.05-0.17)

Yi Yang Xu; Lei Meng; Miao Miao Zhao; Chu Xin Peng; Fei Yen

doi:10.1016/j.jallcom.2023.170685

paper

Electric Polarization and Magnetic Properties of (NH $_{4}$ ) $_{1 - x}$ K $_{x}$ I (x = 0.05-0.17)

arXiv:2405.15261 · doi:10.1016/j.jallcom.2023.170685

Abstract

While all of the polymorphs of pure NH $_{4}$ I and KI are non-polar, we identify that (NH $_{4}$ ) $_{0.95}$ K $_{0.05}$ I is ferroelectric and (NH $_{4}$ ) $_{0.87}$ K $_{0.13}$ I and (NH $_{4}$ ) $_{0.83}$ K $_{0.17}$ I are pyroelectric through measurements of their pyroelectric current and complex dielectric constant. The order to disorder phase transitions occur near 245 K. Magnetic susceptibility measurements indicate that the proton orbitals of the NH $_{4}$ $^{+}$ continue to become ordered in the ground state in the (NH $_{4}$ ) $_{1 - x}$ K $_{x}$ I system up to x <= 0.17. The polar phases are proposed to stem from K $^{+}$ ions disrupting the symmetry of proton-orbital-lattice interactions between the NH $_{4}$ $^{+}$ and I $^{-}$ ions. Our work introduces a new pathway for the ordered phases of ammonium-based compounds to potentially become ferroelectric.

13 pages, 5 figures

Electric Polarization and Magnetic Properties of (NH $_{4}$ ) $_{1 - x}$ K $_{x}$ I (x = 0.05-0.17)

Abstract

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Cited by in corpus (2)

Electric Polarization and Magnetic Properties of (NH4​)1−x​Kx​I (x = 0.05-0.17)

Abstract

References in corpus (3)

Cited by in corpus (2)

Electric Polarization and Magnetic Properties of (NH $_{4}$ ) $_{1 - x}$ K $_{x}$ I (x = 0.05-0.17)