第46回フロンティア材料研究所講演会（Prof. Xiaolong Chen）
| 開催日時 | 2017年09月01日 10:00～11:30 |
|---|---|
| 開催場所 | 元素戦略研究センター（S8棟）１F レクチャーホール |
| 主催 | フロンティア材料研究所 |
| 連絡先 | 細野秀雄 教授 (内線：5009) |
プログラム等
講師： Prof. Xiaolong Chen
（Institute of Physics, Chinese Academy of Sciences）
講演テーマ： Structure and properties of new organic molecule intercalated FeSe superconductors
Abstract:
Here, we report a sonochemical method to synthesize high quality FeSe-based superconductors with organic molecules. Under sonochemical condition, the formation of acoustic cavitation induced transient but extreme local heating in otherwise cold liquids, which stimulate the reaction at low temperatures (~60 °C) without fragment the FeSe layers. We demonstrate that well-crystallized FeSe superconductors can be readily obtained in En, 1,3-DIA and diaminohexane (N,N-DHA) metal solutions within 12 hours, with Tc ~ 46K and superconducting volume fraction up to 91%. Three structural types are found in this series of intercalates, including body-centered tetragonal, body-centered orthorhombic and primary tetragonal. Structure determination is firstly realized based on neutron powder diffraction (NPD) data, which reveals that the Na0.35(7)(C2N2H8)Fe2Se2 compound adopts a tetragonal I4/m structure, in which C2N2H8 molecules have strong disorder in orientation. The redox reactions indicate Na0.35(7)(C2N2H8)Fe2Se2 is stable in air while the alkali metals deintercalate easily. Moreover, a rare tetragonal to orthorhombic structure transition induced by gliding FeSe planes is also probed by high-temperature in-situ diffraction data.
