Phase transitions in Eu doped BiFeO3: High pressure Raman spectroscopy and X-ray diffraction studies

•High pressure structural studies are carried out on Eu doped BiFeO3.•At lower pressures the system goes through two structural transitions.•At extreme pressure a transition to isostructural Imma phase from Pnma is observed.•Phase transitions are found to be driven by release of internal lattice strain.•At about 45 GPa Pnma to Imma transition is accompanied by a sharp drop in volume.

We have studied the high pressure behavior of Bi1−xEuxFeO3Bi1−xEuxFeO3, x=0.05 and 0.1 by powder X-ray diffraction and Raman spectroscopy. High pressure investigations reveal three phase transitions. In the low pressure region the system transforms to the orthorhombic Pnma structure from ambient rhombohedral R3c through coexistence of multiple intermediate phases. Above 45 GPa, we observed a change in symmetry from Pnma to Imma for both the systems. The change in symmetry is driven by the release of strain in the lattice.