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Updated: Nov 25, 2025
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Complex structure and Mössbauer effect observed in the course of phase transitions in PbZr0.72Sn0.28O3 single crystal
Irena Jankowska-Sumara1, Mariola Kądziołka-Gaweł2, Maria Podgórna1
1Institute of Physics, Cracow Pedagogical University, Ul. Podchorążych 2, 30-84 Kraków, Poland.
Abstract:
The Mössbauer effect was used to study the structural transitions in a PbZr0.72Sn0.28O3 single crystal. Two kinds of quadrupole splittings were registered and connected with two different environments of the Sn ion occupying the center of SnO6 octahedra. What is responsible for the existence of these two environments is the disorder in tilts of oxygen octahedra and antiparallel shifts of pairs of lead ions. Both disorders decide on structural transitions which the PbZr0.72Sn0.28O3 single crystal undergoes. The two kinds of quadruple splittings that have been observed do not disappear at temperatures far above phase transitions. This indicates that the structure of the paraelectric phase is locally non-centrosymmetric and confirms pre-transitional effects previously reported for Sn doped PbZrO3 single crystals.
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