Development of Novel Function in Polyoxometalate with Ion Motion

2014 Fiscal Year Final Research Report

• Project/Area Number: 24350095
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Functional materials/Devices
• Research Institution: Hiroshima University
• Principal Investigator: NISHIHARA SADAFUMI 広島大学, 理学(系)研究科(研究院), 准教授 (00405341)
• Co-Investigator(Kenkyū-buntansha): 戸川 欣彦 大阪府立大学, 工学(系)研究科(研究院), 准教授 (00415241) ; 帯刀 陽子 東京農工大学, 工学(系)研究科(研究院), 講師 (30435763) ; 綱島 亮 山口大学, 理工学研究科, 准教授 (70466431)
• Co-Investigator(Renkei-kenkyūsha): INOUE KATSUYA 広島大学, 大学院理学研究科, 教授 (40265731) ; MORI SHIGEO 大阪府立大学, 大学院工学研究科, 教授 (20251613)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 誘電体 / 結晶構造 / ポリオキソメタレート / ランタノイドイオン

Outline of Final Research Achievements

The Pleyssler type Polyoxometalate (POM) has a small cavity wherein not only alkali metal ions, but also lanthanide ions, can be included. Indeed, the Pleyssler type POM including terbium ion has two minimum-potential ion sites inside. In the previous report, it was assumed that two sites are crystallographically equivalent, with an occupancy of 0.5. In this study, we have, however, found the possibility of terbium ion motion between these two ion sites in high temperatures region and it stops gradually with decreasing temperature from the results of temperature dependence of dielectric and IR measurements. In addition, the POM shows ferroelectric behaviour at around ion stopping temperature in the polarization measurements.

Free Research Field

物性化学