在bis-1,2,3-thiaselenazolyl二元体中增强了压力导电性
Leanne Beer1, Jaclyn L Brusso, Robert C Haddon
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|December 22, 2005
概括
新的化物桥接的硫基具有半导体特性. 外部压力显著提高导电性,这表明这些新型材料的过渡向弱金属状态.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 有机电子 有机电子
背景情况:
- 新型异环化合物的合成和表征对于开发新的电子材料至关重要.
- 了解有机基的结构-性质关系是设计先进半导体的关键.
研究的目的:
- 合成和表征N-化二烯桥接的1,2,3-thiaselenazolo-1,2,3-thiaselenazolylium盐及其相应的基因.
- 为了研究这些激进化合物的电子和磁性特性.
- 探索外部压力对它们的导电性的影响.
主要方法:
- 化学和电化学降解硫乙酸以产生基质物种.
- 单晶X射线衍射以确定晶体结构.
- 可变温度的磁性,导电性和近红外光学测量.
- 线性-锡轨道 (LMTO) 带结构计算.
- 在施加的水静压下进行导电性测量.
主要成果:
- 成功合成N-基化化连接的硫盐及其激素形式.
- 激素的晶体呈现出同结构,pi堆叠阵列,具有显著的分子间Se- -Se,Se- -S和Se- -N接触.
- 这些材料表现为小带隙半导体,室温导电率约为10−6 S cm−1.1.
- 外界压力显著增加导电性,在4 GPa时达到10−1 S cm−1 (R1=Me) 和10−2 S cm−1 (R1=Et).
- 在压力下,激活能量显著下降,表明向弱金属状态的过渡.
结论:
- 合成的化物桥接的硫基基是有希望的小带间隙半导体材料.
- 分子间相互作用在它们的固态特性中起着至关重要的作用.
- 外部压力是调整它们电子导电性的有效手段,导致它们接近金属状态.
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