一种单成分分子金属,基于一种二酸黄金复合物
Nadine Tenn1, Nathalie Bellec, Olivier Jeannin
1Sciences Chimiques de Rennes, UMR 6226 CNRS-Universite de Rennes 1, Matiere Condensee et Systemes Electroactifs (MaCSE), Campus de Beaulieu, Bat 10A, 35042 Rennes cedex, France.
Journal of the American Chemical Society
|October 31, 2009
概括
研究人员开发了一种新型的单元分子导体,使用金 bis () 复合物. 这种材料在压力下从半导体转变为金属,为分子电子学提供了新的可能性.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 超分子化学 超分子化学
背景情况:
- 单元分子导体对于先进的电子设备至关重要.
- 开发具有可调节导电性的新材料是一个持续的挑战.
研究的目的:
- 为了分离和描述一种新型的单元分子导体.
- 为了研究材料的压力依赖导电性和电子性质.
主要方法:
- 金 bis ((dithiolene) 复合物的电结晶与N-乙基-1,3-thiazoline-2-thione-4,5-dithiolate (Et-thiazdt) 连接物.
- 进行X射线晶体学以确定晶体结构.
- 可变温度和可变压的导电性测量.
- 第一个原则密度函数理论 (DFT) 计算.
主要成果:
- 一个单元分子导体的隔离,具有1D分子堆的分层结构.
- 该材料在环境条件下是半导体 (0.33 S cm-1),在压力下变为金属,在21 kbar时达到1000 S cm-1.
- 在13 kbar.观察到半导体到金属的交叉.
- DFT计算揭示了一个具有小带间隙的抗铁磁基本状态,模拟解释了压力诱导的导电性变化.
结论:
- 这项工作介绍了第一个具有良好的特征的单元分子金属,不依赖TTF二酸连接体.
- 该材料的导电性对压力高度敏感,显示出一个清晰的途径来稳定金属状态.
- 这些发现为分子导体的设计和控制提供了基本的见解.
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