Phase transitions in perovskite-type relaxor ferroelectrics
Acta Crystallographica Section A: Foundations and advances International Union of Crystallography (IUCr) 58:s1 (2002) c249-c249
Comments on quasicrystalline phases and examples of quasicrystalline phase nomenclature in Nomenclature of magnetic, incommensurate, composition‐changed morphotropic, polytype, transient‐structural and quasicrystalline phases undergoing phase transitions. II. Report of an IUCr Working Group on Phase Transition Nomenclature by J.‐C. Toldano et al. (2001). Acta Cryst. A57, 614–626
Acta Crystallographica Section A: Foundations and advances International Union of Crystallography (IUCr) 58:2 (2002) 209-209
A new view of conoscopic illumination of optically active crystals
JOURNAL OF APPLIED CRYSTALLOGRAPHY 35 (2002) 185-190
Investigation of a peculiar relaxor ferroelectric: Na0.5Bi0.5TiO3.
FERROELECTRICS 270 (2002) 1377-1382
Abstract:
The relaxor ferroelectric, Sodium Bismuth Titanate, (Na0.5Bi0.5TiO3), NBT is an A-site substituted distorted perovskite. An extensive temperature-, pressure- and substitution-dependent study of the crystal structure and phase transitions in this compound has been carried out using neutron/x-ray diffraction techniques. This has been complemented with optical, Raman and computational modelling studies.The temperature-dependent investigation shows that NBT undergoes a first phase transition from the high-temperature cubic prototype (Pm (3) over bar m) Phase I to Phase II of tetragonal symmetry (P4bm) and then a second one with strong diffuse character to Phase III of rhombohedral symmetry (R3c). The high-pressure study of NBT has revealed an interesting and unusual relaxor-to-antiferroelectric (R3c --> Pnma) phase transition. Structural variations as a function of temperature and doping across the (Na1-xKx)(0.5)Bi0.5TiO3 (NKBT) series have also been established.Nomenclature of magnetic, incommensurate, composition-changed morphotropic, polytype, transient-structural and quasicrystalline phases undergoing phase transitions.: II.: Report of an IUCr Working Group on Phase Transition Nomenclature (vol A57, pg 614, 2001)
ACTA CRYSTALLOGRAPHICA SECTION A 58 (2002) 79-79