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. Tolédano et al. (2001). Acta Cryst. A57, 614-626.
Acta crystallographica. Section A, Foundations of crystallography 58:Pt 2 (2002) 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