A-site doping-induced renormalization of structural transformations in the PbSc{sub 0.5}Nb{sub 0.5}O{sub 3} relaxor ferroelectric under high pressure

Journal Article · Sat May 01 00:00:00 EDT 2010 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.81.174116· OSTI ID:21366814

Maier, B J; Welsch, A -M; Mihailova, B; Paulmann, C; Bismayer, U ^[1]; Angel, R J; Zhao, J ^[2]; Engel, J M ^[3]; Schmitt, L A ^[4]; Gospodinov, M ^[5]; Friedrich, A ^[6]

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1. Department Geowissenschaften, Universitaet Hamburg, Grindelallee 48, D-20146 Hamburg (Germany)
2. Virginia Tech Crystallography Laboratory, Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24060 (United States)
3. Institut fuer Werkstoffwissenschaften, Technische Universitaet Dresden, Helmholtzstr. 7, D-01069 Dresden (Germany)
4. Materials Science Structure Research, Universitaet Darmstadt, Petersenstr. 23, D-64287 Darmstadt (Germany)
5. Institute of Solid State Physics, Bulgarian Academy of Sciences, Boulevard Tzarigradsko Chausse 72, 1784 Sofia (Bulgaria)
6. Institut fuer Geowissenschaften, Goethe-Universitaet, Altenhoeferallee 1, D-60438 Frankfurt am Main (Germany)

The effect of A-site incorporated Ba{sup 2+} and Bi{sup 3+} on the pressure-driven structural transformations in Pb-based perovskite-type relaxor ferroelectrics has been studied with in situ x-ray diffraction and Raman scattering of PbSc{sub 0.5}Nb{sub 0.5}O{sub 3}, Pb{sub 0.93}Ba{sub 0.07}Sc{sub 0.5}Nb{sub 0.5}O{sub 3}, and Pb{sub 0.98}Bi{sub 0.02}Sc{sub 0.51}Nb{sub 0.49}O{sub 3} in the range from ambient pressure to 9.8 GPa. The substitution of Ba{sup 2+} for Pb{sup 2+} represents the case in which A-site divalent cations with stereochemically active lone-pair electrons are replaced by isovalent cations with a larger ionic radius and no active lone pairs, leading to formation of strong local elastic fields. In contrast, substitution of Bi{sup 3+} for Pb{sup 2+} involves the replacement of divalent A-site cations with active lone-pair electrons by aliovalent cations with nearly the same ionic radius and active lone pairs so it induces local electric fields but not strong elastic fields. The two types of dopants have rather distinct effects on the changes in the atomic structure under pressure. The embedding of Ba{sup 2+} and associated elastic fields hinders the development of pressure-induced ferroic ordering and thus smears out the phase transition. The addition of Bi{sup 3+} enlarges the fraction of spatial regions with a pressure-induced ferroic distortion, resulting in a more pronounced phase transition of the average structure, i.e., the preserved lone-pair order and the absence of strong local elastic fields enhances the development of the ferroic phase at high pressure. For all compounds studied, the high-pressure structure exhibits glide-plane pseudosymmetry associated with a specific octahedral tilt configuration.

• OSTI ID: 21366814
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 81, Issue 17; Other Information: DOI: 10.1103/PhysRevB.81.174116; (c) 2010 The American Physical Society; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
BARIUM IONS
BISMUTH IONS
CONFIGURATION
DOPED MATERIALS
ELASTICITY
ELECTRIC FIELDS
ELECTRONS
FERROELECTRIC MATERIALS
LEAD COMPOUNDS
LEAD IONS
NIOBIUM COMPOUNDS
OXYGEN COMPOUNDS
PEROVSKITE
PHASE TRANSFORMATIONS
PRESSURE RANGE GIGA PA
RAMAN EFFECT
RENORMALIZATION
SCANDIUM COMPOUNDS
SCATTERING
X-RAY DIFFRACTION
CHARGED PARTICLES
COHERENT SCATTERING
DIELECTRIC MATERIALS
DIFFRACTION
ELEMENTARY PARTICLES
FERMIONS
IONS
LEPTONS
MATERIALS
MECHANICAL PROPERTIES
MINERALS
OXIDE MINERALS
PEROVSKITES
PRESSURE RANGE
REFRACTORY METAL COMPOUNDS
TRANSITION ELEMENT COMPOUNDS