Structural stability of multiferroic BiFeO3

Multiferroic BiFeO3 was fabricated via a high pressure of 5GPa at 900 degrees C. The crystal structure of the BiFeO3 ceramic was determined by X-ray diffraction (XRD) to be a rhombohedral perovskite with a space group of R3c. The temperature dependence of XRDs was collected down to 5K under ambient pressure that showed no structure phase transition. The structural evolution of BiFeO3 under high pressures up to 56.6GPa was studied at room temperature using a diamond anvil cell combined with synchrotron radiation XRD. A possible phase transition was proposed at around 10GPa. The bulk modulus was estimated to be B0=97.3(7)GPa in the low-pressure range.