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Elastic Constants and Charge Ordering in a'-NaV2O5

H. Schwenk·S. Zherlitsyn·B. Luethi·E. Morre·C. Geibel
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Abstract

We present the temperature dependence of shear and longitudinal elastic constants in a'-NaV2O5. For the longitudinal c22 and c33 modes we find anomalies at Tc in contrast to the Spin Peierls substance CuGeO3 where only the longitudinal mode along the chain shows a pronounced effect at TSP. The c66 shear mode (propagation along the chain in b-direction polarization in a-direction) shows strong softening of 12%. Such a large effect is absent for all shear modes in CuGeO3. We can interpret this softening with a coupling of the exy symmetry strain to the charge fluctuation of B1g symmetry. We give the possible low temperature charge distribution.

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H. Schwenk, S. Zherlitsyn, B. Luethi, E. Morre, C. Geibel. 1999-04-23. Elastic Constants and Charge Ordering in a'-NaV2O5. https://doi.org/10.1103/physrevb.60.9194

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