Now showing items 1-10 of 10

    • The ferroelectric phase of CdTiO3. A powder neutron diffraction study. 

      Kennedy, Brendan J; Zhou, Qingdi; Avdeev, Maxim (Elsevier, 2011)
      The synthesis of bulk samples of polycrystalline CdTiO3 in both the rhombohedral ilmenite and orthorhombic perovskite forms is described and the structures of these have been refined using powder neutron diffraction data. ...
    • The impact of anion ordering on octahedra distortion and phase transitions in SrTaO2N and BaTaO2N 

      Wang, Chun-Hai; Kennedy, Brendan J; Menezes de Oliveira, Andre; Polt, Julia; Knight, Kevin S (IUCr, 2017)
      In this work, we synthesized BaTaO2N and SrTaO2N using a two-step high temperature solid state reaction method and analysed the structural distortions, relative to the ideal cubic perovskite structure, according to group ...
    • Low temperature structure and the ferroelectric phase transitions in the CdTiO3 perovskite 

      Kennedy, Brendan J; Zhou, Qingdi; Zhao, Shipeng; Jia, Fanhao; Ren, Wei; Knight, Kevin S (Amercian Physical Society, 2017)
      The paraelectric-ferroelectric transition in CdTiO3 has been monitored using high resolution neutron diffraction data. This necessitated preparing a sample enriched in 114Cd. A subtle, but significant, anisotropy in the ...
    • Magnetic and structural studies of Sc containing ruthenate double perovskites A2ScRuO6 (A = Ba, Sr). 

      Kayser, Paula; Injac, Sean; Ranjbar, Ben; Kennedy, Brendan J; Avdeev, Maxim; Yamaura, Kazunari (ACS, 2017)
      Ruthenium containing double perovskites A2ScRuO6 have been synthesized as polycrystalline powders and structurally characterized using a combination of synchrotron X-ray and neutron powder diffraction methods. When A = ...
    • Multi-scale Structural Analysis of the A-site and Oxygen Deficient Perovskite Sr11Mo4O2 

      King, Graham; Avdeev, Maxim; Qasim, Ilyas; Zhou, Qingdi; Kennedy, Brendan J (Royal Society of Chemistry, 2017)
      The long range average crystal structure, as well as the short and medium range structural features, of the A-site deficient and oxygen deficient perovskite Sr11Mo4O23 have been determined. Rietveld refinement of synchrotron ...
    • Spin-orbit coupling controlled ground state in the Ir(V) perovskites A2ScIrO6 (A = Ba or Sr) 

      Kayser, Paula; Kennedy, Brendan J; Ranjbar, Ben; Kimpton, Justin; Avdeev, Maxim (ACS, 2017)
      The structural and magnetic properties of the two Ir(V) perovskites Ba2ScIrO6 and Sr2ScIrO6 have been established. The structures were refined using a combined neutron and Synchrotron data set. At room temperature the ...
    • Structural and magnetic properties of the osmium double perovskites Ba2-xSrxYOsO6 

      Kayser, Paula; Injac, Sean; Kennedy, Brendan J; Vogt, Thomas; Avdeev, Maxim; Maynard-Casely, Helen; Zhaoming, Zhang (ACS, 2017)
      The crystal and magnetic structures of double perovskites of the type Ba2-xSrxYOsO6 have been studied by synchrotron X-ray and neutron powder diffraction methods, bulk magnetic susceptibility measurements and X-ray absorption ...
    • Structure and Magnetism in Sr1-xAxTcO3 Perovskites. The importance of the A-site cation. 

      Reynolds, Emily; Avdeev, Maxim; Thorogood, Gordon J; Poineau, Frederic; Czerwinski, Kenneth R; Kimpton, Justin A; Yu, Michelle; Kayser, Paula; Kennedy, Brendan J (Amercian Physical Society, 2017)
      The Sr1-xBaxTcO3 (x = 0, 0.1, 0.2) oxides were prepared and their solid-state and magnetic structure studied as a function of the temperature by x-ray and neutron powder diffraction. The refined Tc moments at room temperature ...
    • Thermal Expansion Behavior in TcO2. Towards breaking the Tc-Tc bond. 

      Reynolds, Emily; Zhang, Zhaoming; Avdeev, Maxim; Thorogod, Gordon J; Poineau, Frederic; Czerwinski, Kenneth R; Kimpton, Justin A; Kennedy, Brendan J (ACS, 2017)
      The structure of TcO2 between 25 and 1000 °C has been determined in-situ using powder diffraction methods and is found to remain monoclinic in space group P21/c. The thermal expansion in TcO2 is highly anisotropic with ...
    • Thermal Expansion in BaRuO3 Perovskites – an unusual case of bond strengthening at high temperatures 

      Kayser, Paula; Injac, Sean; Kennedy, Brendan J; Menezes de Oliveira, Andre; Shirako, Yuichi; Hasegawa, Masashi (RSC, 2017)
      The temperature dependence of the structures of three polytypes of BaRuO3 have been investigated between room temperature and 1000 °C using high resolution Synchrotron X-ray diffraction. The structural studies reveal a ...