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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
一个bisdithiazolyl基和其高价值的σ-二元体之间的歇斯底里旋转交叉
Kristina Lekin1, Stephen M Winter, Laura E Downie
1Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
Journal of the American Chemical Society
|October 23, 2010
概括
比斯迪西亚醇基1a表现出二态性,具有明显的α和β相. 该β相经历了可逆的温度和压力诱导的从二磁二次体到偏磁基态的转变.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 双亚醇基1a存在于两个晶体形式:α和β.
- α阶段的特征是 π 堆叠的基,而 β阶段由 π 堆叠的二元组成,由 S··S-S··S σ 键连接在一起.
研究的目的:
- 为了研究二形 bisdithiazolyl 基1a. 的结构性,磁性和导电性质.
- 阐明温度和压力诱导的β相相转换的性质.
主要方法:
- 可变温度磁感应度的测量.
- 在不同温度和压力下的粉末X射线衍射 (XRD).
- 可变温度和压力导电性测量.
主要成果:
- 该α相表现为库里-斯磁铁,在低温下表现出1D海森堡链反铁磁合.
- 该β相是二磁性高达380K,通过二次到根的转换过渡到一个偏磁状态.
- 在β-1a中相变是由温度 (380K) 和压力 (0.650.98GPa) 触发的,涉及S·S-S·S·S σ-键的裂变.
- 这两个阶段都表现出绝缘性行为,在压力下导电性显著增强,特别是在过渡期间的β阶段.
结论:
- 双形 bisdithiazolyl 基1a 的二态性导致了不同的磁性和电子性质.
- β相表现出一种独特的可逆的二元到基相位过渡,由热和机械刺激驱动.
- 这项研究强调了分子间结合在决定激进系统的固态行为中的关键作用.
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