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arXiv · 1208.4499

Two types of adjacent dimer layers in the low temperature phase of BaCuSi2O6

D. V. Sheptyakov·V. Yu. Pomjakushin·R. Stern·I. Heinmaa·H. Nakamura·T. Kimura
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Abstract

The low-temperature crystal structure of BaCuSi2O6 has been investigated with high-resolution synchrotron x-ray and neutron powder diffraction techniques and has been found to be on average (ignoring the incommensurate modulation) orthorhombic, with the most probable space group Ibam. The Cu-Cu dimers in this material are forming two types of layers with distinctly different interatomic distances. Subtle changes also modify the partially frustrated interlayer Cu-Cu exchange paths. The present results corroborate the interpretation of low-temperature nuclear magnetic resonance and inelastic neutron scattering data in terms of distinct dimer layers.

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D. V. Sheptyakov, V. Yu. Pomjakushin, R. Stern, I. Heinmaa, H. Nakamura, T. Kimura. 2012-08-22. Two types of adjacent dimer layers in the low temperature phase of BaCuSi2O6. https://doi.org/10.1103/physrevb.86.014433

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