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Magnetic-induced phonon anisotropy in ZnCr$_2$O$_4$ from first principles

Craig J. Fennie·Karin M. Rabe
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Abstract

We have studied the influence of magnetic order on the optical phonons of the geometrically frustrated spinel ZnCr$_2$O$_4$ from first-principles. By mapping the first-principles phonon calculations onto a Heisenberg-like model, we developed a method to calculate exchange derivatives and subsequently the spin-phonon couping parameter from first-principles. All calculations were performed within LSDA+U.

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Craig J. Fennie, Karin M. Rabe. 2006-02-21. Magnetic-induced phonon anisotropy in ZnCr$_2$O$_4$ from first principles. https://doi.org/10.1103/physrevlett.96.205505

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