Equation of state and structural transition at high hydrostatic pressures in the BiFeO[subscript 3] crystal

Journal Article · Wed Oct 29 04:00:00 EDT 2008 · JETP Lett.

DOI:https://doi.org/10.1134/S0021364007150106· OSTI ID:1007674

Gavriliuk, A G; Struzhkin, V V; Lyubutin, I S; Troyan, I A ^[1]

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1. Russ. Acad. Sci.

Change in the crystal structure of the BiFeO{sub 3} multiferroic at high pressures up to 70 GPa in a diamond anvil cell has been studied by the method of synchrotron x-ray diffraction at room temperature. The experiment has been carried out under hydrostatic conditions with helium as a pressure-transferring medium. An anomaly has been observed in the behavior of the structural parameters at pressures P{sub c} {approx} 40-50 GPa. This anomaly correlates with the effect of the magnetic collapse of iron moments revealed in this pressure range. It has been found that the bulk compression modulus is equal to B{sub 0} = (75.5 {+-} 15.5) GPa in the interval 0 < P < P{sub c} and is almost quadrupled to a value of B = (292 {+-} 9) GPa in the interval P > P{sub c}. When the pressure decreases, the behavior of the structural parameters is completely reversible in correlation with the reversibility of the magnetic transition. The 'diffuseness' of the structural transition in pressure is explained by thermal fluctuations between the high-and low-spin states of Fe{sup 3+} ions in the transition region.

• Research Organization: Advanced Photon Source (APS), Argonne National Laboratory (ANL), Argonne, IL (US)
• Sponsoring Organization: USDOE
• OSTI ID: 1007674
• Journal Information: JETP Lett., Journal Name: JETP Lett. Journal Issue: (3) ; 10, 2007 Vol. 86; ISSN 0021-3640
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
43 PARTICLE ACCELERATORS
COMPRESSION
CRYSTAL STRUCTURE
DIAMONDS
FLUCTUATIONS
HELIUM
HYDROSTATICS
IRON
PRESSURE RANGE
SYNCHROTRONS
X-RAY DIFFRACTION