A possible demonstration of cooperative dynamical Jahn-Teller effect in Raman scattering spectrum of rhombohedral $LaMnO_3$

S. E. Popov; A. E. Nikiforov

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A possible demonstration of cooperative dynamical Jahn-Teller effect in Raman scattering spectrum of rhombohedral $LaMnO_3$

S. E. Popov·A. E. Nikiforov

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Abstract

The Raman scattering (RS) spectra of rhombohedral $LaMnO_3$ is considered. It is shown that broad high intensity RS line at 640 $cm^{-1}$ could be explained in the framework of cooperative dynamical Jahn-Teller effect. This hypothesis is illustrated through the lattice dynamics calculations explicitly allowing for the electron-phonon term both in crystal energy and in dynamical matrix. The averaging scheme for the one mode cooperative dynamical effect is proposed

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S. E. Popov, A. E. Nikiforov. 2003-07-02. A possible demonstration of cooperative dynamical Jahn-Teller effect in Raman scattering spectrum of rhombohedral $LaMnO_3$. https://arxiv.org/abs/cond-mat/0307036

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