原型的dithiazolodithiazolyl基:合成,结构和运输特性
Leanne Beer1, James F Britten, Jaclyn L Brusso
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|November 20, 2003
概括
新的合成路径产生了新的1,2,3-dithiazolo-1,2,3-dithiazolylium盐. 这些材料表现出偏磁性质和半导体行为,表明莫特-哈巴德绝缘体的基本状态.
科学领域:
- 材料科学 材料科学 材料科学
- 有机化学 有机化学
- 固态物理 固态物理
背景情况:
- 1,2,3-dithiazolo-1,2,3-dithiazolylium盐是一种有趣电子性质的有机化合物.
- 开发新的合成路径对于访问具有可调性特征的新材料至关重要.
研究的目的:
- 开发用于1,2,3-dithiazolo-1,2,3-dithiazolylium盐的新合成方法.
- 描述合成的激素化合物的电子和结构性质.
- 研究它们作为有机导体的潜力.
主要方法:
- 双赫兹凝结反应使用N-化2,6-氨二盐和硫单化物.
- 循环电压测量和EPR光谱用于溶液的表征.
- 为了固态结构的确定,使用X射线晶体学.
- 磁性,导电性和光学测量.
- 扩展的Hückel波段计算.
主要成果:
- 成功合成了新型的1,2,3-dithiazolo-1,2,3-dithiazolylium盐.
- 在溶液中的两个原型基 (HBPMe和HBPEt) 的表征.
- 晶体结构显示了滑落的pi-stacks与密切的分子间S-S接触.
- 在100 K以上观察到的偏磁性行为.
- 室温导电性在10~5~10~6S cm~-1) 范围内.
结论:
- 合成的材料表现出与Mott-Hubbard绝缘体基本状态一致的特性.
- 建议在现场使用较低的库伦比克排斥能量 (U),大约为1.0 eV.
- 电子特性受到晶体包装和分子间相互作用的影响.
相关概念视频
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Introduction
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01:29Diels–Alder Reaction: Characteristics of Dienes
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Characteristics of the diene
Conformation
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Characteristics of the diene
Conformation
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01:20Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
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01:11Aryldiazonium Salts to Azo Dyes: Diazo Coupling
The reaction of weakly electrophilic aryldiazonium (also called arenediazonium) salts with highly activated aromatic compounds leads to the formation of products with an —N=N— link, called an azo linkage. This reaction, presented in Figure 1, is known as diazo coupling and occurs without the loss of the nitrogen atoms of the aryldiazonium salt. Highly activated aromatic compounds such as phenols or arylamines favor the diazo coupling reaction. The coupling generally occurs at the para position.
01:29Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry
Diels–Alder reactions between cyclic dienes locked in an s-cis configuration and dienophiles yield bridged bicyclic products.