Ferroelectric-paraelectric transition in BiFeO3: crystal structure of the orthorhombic beta phase.
A detailed investigation using variable temperature powder neutron diffraction demonstrates that BiFeO3 undergoes a phase transition from the ferroelectric alpha phase (rhombohedral, R3c) to a paraelectric beta phase (orthorhombic, Pbnm) between 820 degrees C and 830 degrees C. Coexistence of both phases over a finite temperature interval, together with abrupt changes in key structural parameters, confirms that the transition is first order. The beta phase corresponds to a GdFeO3-type perovskite structure.
Arnold
Donna C
DC
School of Chemistry, University of St. Andrews, North Haugh, St. Andrews, Fife, KY16 9ST, United Kingdom.
Knight
Kevin S
KS
Morrison
Finlay D
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Lightfoot
Philip
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