EXAFS study of LiV₂O₄ under high pressure

Abstract

The EXAFS analysis of LiV₂O₄, under pressure, is discussed. Subtle changes observable above 13 GPa suggest that a charge-ordering state is induced at high pressure. This state is probably similar to the one recently discussed by Katsufuji and coworkers [T. Katsufuji et al., Phys. Rev. Lett. 96 086046 (2006).] for a similar compound, which proposed the formation of “vanadium molecules” in a geometrically frustrated crystal.

Keywords:

• X-ray absorption spectra
• Charge-ordered compound
• High pressure

Acknowledgements

This research project has been supported by the European Commission under the 6th Framework Programme through the Key Action: strengthening the European research area, research infrastructures, contract no. RII3-CT-2004-506008. This work was performed at the Swiss Light Source, Paul Scherrer Institut, Villigen, Switzerland. We are grateful to the machine and beamline groups whose outstanding efforts have made these experiments possible.

Notes

^†X-ray diffraction on the single crystals obtained confirmed the proposed structure and gave a lattice parameter a=8.227 Å at R=1.9%. This value was considered for the calculation of the distances, see later.

^‡AlV₂O₄ is isostructural and has closely related lattice parameters, a=8.192: B. Reuter, R. Aust, G. Colsmann et al., Zeitschrift fur Anorg. Allg. Chem. 500 188–198 (1983).