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The effect of Cu substitution on the A1g mode of La(0.7)Sr(0.3)MnO3 manganites

G. De Marzi·H. J. Trodahl·J. Bok·A. Cantarero·F. Sapina
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Abstract

We report on the first Raman data of Cu substituted La(1-y)Sr(y)Mn(1-x)Cu(x)O3 (0 < x < 0.10 and 0.17 < y < 0.3, accordingly in order to have the same Mn(4+)/[Mn(4+)+Mn(3+)] ratio), collected in the frequency range 100-900 cm-1 and at room temperature, with parallel and crossed polarizations of the incident and scattered light. Spectra were fitted with a Drude-Lorentz model, and peaks at 190-220 and 430 cm-1, together with two broad structures centered at near 500 and 670 cm-1, have been found. We also have observed that the A1g mode is substantially shifted with increasing Cu substitution. The A1g phonon shift is a linear function of the tolerance factor t and the rhombohedral angle, thus following the structural changes of the MnO6 octahedra in the system.

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G. De Marzi, H. J. Trodahl, J. Bok, A. Cantarero, F. Sapina. 2003-05-14. The effect of Cu substitution on the A1g mode of La(0.7)Sr(0.3)MnO3 manganites. https://doi.org/10.1016/s0038-1098(03)00423-x

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