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 |
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| Section | 一般 |
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| Research Field |
Inorganic materials/Physical properties
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| Research Institution | Nagoya Institute of Technology |
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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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| Project Status |
Completed (Fiscal Year 2013)
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| Budget Amount *help |
¥18,070,000 (Direct Cost: ¥13,900,000、Indirect Cost: ¥4,170,000)
Fiscal Year 2012: ¥5,720,000 (Direct Cost: ¥4,400,000、Indirect Cost: ¥1,320,000)
Fiscal Year 2011: ¥5,850,000 (Direct Cost: ¥4,500,000、Indirect Cost: ¥1,350,000)
Fiscal Year 2010: ¥6,500,000 (Direct Cost: ¥5,000,000、Indirect Cost: ¥1,500,000)
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| Keywords | 構造科学 / 無鉛強誘電体 / 単結晶精密構造解析 / 自発分極 / 構造相転移 / 炭酸カルシウム / 分域構造 / 斜方晶 / 正方晶 / 立法晶 / ニオブ酸カリウムナトリウム / 自発公極 |
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| 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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Report
(4 results)
Research Products
(64 results)
