IR vibrational modes and spin-phonon interplay in magnetoelectric LiNiPO4
Autor: | M. S. Radionov, S. A. Klimin, A. Yu. Glamazda, A. V. Peschanskii |
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Rok vydání: | 2022 |
Předmět: | |
Zdroj: | Low Temperature Physics. 48:246-252 |
ISSN: | 1090-6517 1063-777X |
Popis: | LiNiPO4, multifunctional material with potential ionic current and magnetoelectric applications, was studied by IR optical spectroscopy and lattice dynamic shell-model calculations. We present IR phonon parameters of lithium-nickel-phosphate, both experimental (at T = 30 K) and calculated ones. Multiferroic properties of lithium-nickel-phosphate were confirmed by temperature evolution of phonon band parameters due to spin-phonon interaction revealed for a number of phonon modes. The most pronounced effect was registered for B2 u IR-vibrational mode near 202 cm−1, which demonstrates anomalous temperature behavior in the vicinity of magnetic ordering ( TN = 21.8 K) indicating the coupling to the magnetic subsystem. This mode is assigned to the complex normal vibration including the librations of the PO4 tetrahedra, out-of-plane vibrations of the Li atoms, and the in-plane vibrations of the magnetic Ni atoms along the b axis. The detected phonon shift at TN can be explained by the striction phenomena. |
Databáze: | OpenAIRE |
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