"Pressure-induced phase transition and octahedral tilt system change of Ba2BiSbO6"
M.W. Lufaso, R.B. Macquart, Y. Lee, T. Vogt, H-C. zur Loye
Journal of Solid State Chemistry
Vol.179, No.3, pp.917-922, 2006.03
High-resolution X-ray synchrotron powder diffraction studies under high-pressure conditions are reported for the ordered double perovskite Ba2BiSbO6. Near 4 GPa, the oxide undergoes a pressure-induced phase transition. The symmetry of the material changes during the phase transition from space group to space group I2/m, which is consistent with a change in the octahedral tilting distortion from an a−a−a− type to a0b−b− type using the Glazer notation. A fit of the volume–pressure data using the Birch–Murnagaham equation of state yielded a bulk modulus of 144(8) GPa for the rhombohedral phase.