| 研究領域 | 配位アシンメトリー：非対称配位圏設計と異方集積化が拓く新物質科学 |
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| 研究課題/領域番号 |
19H04590
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| 研究種目 |
新学術領域研究(研究領域提案型)
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| 配分区分 | 補助金 |
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| 審査区分 |
理工系
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| 研究機関 | 大阪府立大学 |
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研究代表者 |
プラシデス コスマス 大阪府立大学, 工学(系)研究科(研究院), 教授 (90719006)
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| 研究期間 (年度) |
2019-04-01 – 2021-03-31
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| 研究課題ステータス |
完了 (2020年度)
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| 配分額 *注記 |
4,940千円 (直接経費: 3,800千円、間接経費: 1,140千円)
2020年度: 2,470千円 (直接経費: 1,900千円、間接経費: 570千円)
2019年度: 2,470千円 (直接経費: 1,900千円、間接経費: 570千円)
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| キーワード | mixed valence / valence transitions / spin frustration / rare earths / fullerides / Asymmetric assembly / pi-electron systems / spherical molecules / planar molecules / bowl-shaped molecules |
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| 研究開始時の研究の概要 |
The project will develop a new molecular materials platform using metal-dictated asymmetric assembly of spherical, planar and curved nanocarbons into unconventional high-Tc superconductors and quantum magnets. It will fuse molecular solid state chemistry and materials physics and follows two inter-related parts:
(A) Asymmetric assembly of electronically active units in dynamically-flexible metal-directed extended structures of variable dimensionality.
(B) Employing chemical and physical means to unveil, control and enhance electronic, conducting, and magnetic functionalities.
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| 研究実績の概要 |
Research focused on asymmetrically coordinated (cationogenic and anionogenic) mixed valence molecular solids. Progress was achieved in producing magnetically frustrated spin assemblies and driving insulator-to-metal transitions by valence transitions via the application of external stimuli.
[1] The electronic properties of d- and f-shell materials have drawn the bulk of research attention but although unconventional p-electron-based electronic, magnetic and conducting materials are rare, they are a fascinating topic. Among alkali oxides, the molecular sesquioxides A4O6 (A = alkali metal) are of special interest as they are rare examples of binary ionic compounds with molecular dioxygen in two different oxidation states. Our work has unveiled a complex cubic (charge-disordered) to tetragonal (charge-ordered) stability phase space as a function of temperature and pressure together with an intimate link between the lattice geometry and the absence of long-range magnetic ordering, which is
suppressed because of geometric frustration.
[2] Rare-earth (RE) fullerides are an intriguing family of materials in which RE electronic instabilities couple to the electronic and lattice degrees-of-freedom of the strongly-correlated C60 sublattice. We revealed that the asymmetrically-coordinated mixed-valency (Sm1-xCax)2.75C60 materials show pressure-driven reversible phase transitions accompanied by drastic increases in Sm valence and C60 oxidation state. These are coincident with huge lattice contractions and concomitant insulator-to-metal transitions.
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| 現在までの達成度 (段落) |
令和2年度が最終年度であるため、記入しない。
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| 今後の研究の推進方策 |
令和2年度が最終年度であるため、記入しない。
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