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Magnetic interactions and the pressure phase-diagram of CuGeO3

P. H. M. van Loosdrecht·J. Zeman·G. Martinez·G. Dhalenne·A. Revcolevschi·.
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Abstract

A pressure and temperature dependent Raman study of the vibrational and spin dynamics in CuGeO3 is presented. A new low temperature, high pressure phase has been identified, and a pressure-temperature phase-diagram is proposed for CuGeO3. The pressure dependence of the effective exchange interaction, of the spin-Peierls gap, and of the spin-Peierls temperature strongly supports a model in which next nearest neighbor interactions stabilise the SP ground state. The Raman data allow for a quantitative estimate of the pressure dependence of the next nearest neighbor interactions.

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P. H. M. van Loosdrecht, J. Zeman, G. Martinez, G. Dhalenne, A. Revcolevschi, .. 1996-12-20. Magnetic interactions and the pressure phase-diagram of CuGeO3. https://doi.org/10.1103/physrevlett.78.487

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