Low temperature structural phase transition of Ba3NaIr2O9
Single crystal X-ray and synchrotron X-ray powder diffraction have been used to probe the structure of Ba3NaIr2O9 from 300 K down to 20 K. Ba3NaIr2O9 is found to undergo a structural transition from hexagonal symmetry, P63/mmc, at ambient temperature to monoclinic symmetry, C2/c, at low temperature. The evolution of the unit cell volume upon cooling is indicative of a higher order structural transition, and the symmetry breaking becomes apparent as the temperature is decreased. The low temperature monoclinic structure of Ba3NaIr2O9 contains strongly distorted [NaO6] and [IrO6] octahedra in comparison to the room temperature hexagonal structure.
Published in Solid State Sciences, Volume 11, Issue 3, 2009, pages 608-613.
© Solid State Sciences 2009, Elsevier
zur Loye, H.-C, Macquart, R. B., Kim, S.-J., Smith, M. D., Lee, Y., Vogt, T.,(2009). Low temperature structural phase transition of Ba3NaIr2O9, 11(3), 608-613