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Structural Phase Transition in the 2D Spin Dimer Compound SrCu2(BO3)2

K. Sparta·G. J. Redhammer·P. Roussel·G. Heger·G. Roth·P. Lemmens·A. Ionescu·M. Grove·G. Guentherodt·F. Huening·H. Lueken·H. Kageyama·K. Onizuka·Y. Ueda
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Abstract

A displacive, 2nd order structural phase transition at Ts=395 K from space group I`4 2 m below Ts to I 4/m c m above Ts has been discovered in the two-dimensional spin dimer compound SrCu2(BO3)2. The temperature evolution of the structure in both phases has been studied by X-ray diffraction and Raman scattering, supplemented by differential scanning calorimetry and SQUID magnetometry. The implications of this transition and of the observed phonon anomalies in Raman scattering for spin-phonon and interlayer coupling in this quantum spin system will be discussed.

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K. Sparta, G. J. Redhammer, P. Roussel, G. Heger, G. Roth, P. Lemmens, A. Ionescu, M. Grove, G. Guentherodt, F. Huening, H. Lueken, H. Kageyama, K. Onizuka, Y. Ueda. 2000-12-20. Structural Phase Transition in the 2D Spin Dimer Compound SrCu2(BO3)2. https://doi.org/10.1007/s100510170296

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