2013 Fiscal Year Final Research Report
Structural study on the phase transition and physical properties of alkaline niobate-type ferroelectric compounds
Project/Area Number |
22360272
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Inorganic materials/Physical properties
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Research Institution | Nagoya Institute of Technology |
Principal Investigator |
ISHIZAWA Nobuo 名古屋工業大学, 工学(系)研究科(研究院), 教授 (90151365)
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Co-Investigator(Renkei-kenkyūsha) |
KAKIMOTO Ken-ichi 名古屋工業大学, 工学研究科, 教授 (40335089)
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Project Period (FY) |
2010-04-01 – 2013-03-31
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Keywords | 構造科学 |
Research Abstract |
Phase transitions and associated changes in physical properties of the alkaline niobate ferroelectric single-crystals, have been investigated from a structural point of view. A high-precision single-crystal X-ray diffraction study at elevated temperatures revealed a systematic change in the coordination number of niobium atoms and the spontaneous polarization. The anharmonic atomic displacement parameters of the paraelectric cubic phase were determined from the Gram-Charlier expansion series, in order to obtain the joint-probability density function and the one-particle potential. These analyses revealed a presence of strong one-dimensional correlation of O atoms along the -O-Nb-O-Nb- chain, suggesting possible nucleation and growth of small tetragonal ferroelectric domains in the paraelectric matrix of the cubic phase just above the phase transition point. Structural studies were also carried out on the related compounds.
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