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arXiv · 0704.1402

IR-active optical phonons in Pnma-1, Pnma-2 and R3c phases of LaMnO_{3+δ}

I. S. Smirnova·A. V. Bazhenov·T. N. Fursova·A. V. Dubovitskii·L. S. Uspenskaya·M. Yu. Maksimuk
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Abstract

Infrared-active phonons in LaMnO_{3+δ} were studied by means of the reflection and transmission spectroscopy from 50 to 800 cm^{-1} at room temperature. Powder and ceramic samples of the phases of Pnma-2 (δ=0.02), Pnma-1 (δ=0.08), and R3c (δ=0.15) were investigated. Besides, energies of the dipole-active phonons in Pnma-2, Pnma-1 phases were obtained by lattice-dynamics calculations. The transformations of IR-active phonons with the increase of δin the sequence of Pnma-2, Pnma-1, R3c are discussed.

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I. S. Smirnova, A. V. Bazhenov, T. N. Fursova, A. V. Dubovitskii, L. S. Uspenskaya, M. Yu. Maksimuk. 2007-04-23. IR-active optical phonons in Pnma-1, Pnma-2 and R3c phases of LaMnO_{3+δ}. https://doi.org/10.1016/j.physb.2008.07.008

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