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Updated: Apr 29, 2026

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热,压力和光引起的bisdithiazolyl基和二聚体的相互转换

Kristina Lekin¹, Hoa Phan, Stephen M Winter

¹Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.

Journal of the American Chemical Society

|May 24, 2014

概括

这项研究揭示了 bisdithiazolyl 基二极体如何表现出对压力和光的独特反应. 一个二极体在压力下是稳定的,而两者都可以被光分解,由此产生的根对的热稳定性各不相同.

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:

这项研究研究了异环 bisdithiazolyl 激素及其二元体的固态特性.
了解根基系统的结构和电子行为对于开发新型电子材料至关重要.

研究的目的:

为了探索 bisdithiazolyl 基质二极体的压力和光学诱导的转化.
为了比较不同二元相 (α和β) 和相关化合物 (1b与1a) 的稳定性和解离机制.
用计算方法阐明管理这些相互转换的电子结构.

主要方法:

在可变温度和高压下单晶X射线衍射.
可变温度磁感应度的测量.
光学光谱学 (UV-Vis). 在光学光谱学 (UV-Vis).
密度函数理论 (DFT) 和完整主动空间自相一致场 (CAS-SCF) 的计算.

主要成果:

比斯迪醇基1b的α相表现出滑落的π结构,而β相则形成具有高价值S··S键的二元体.
β相二极子 (β-1b) 是二磁性,并且可以抵抗高达400K的热解离和高达8GPa的压力.
相比之下,相关的二元体β-1a在0.8 GPa时很容易分裂成基.
可见光辐射将两种二分体解离成基对,它们在恢复到二分体状态之前持续到特定的温度 (150 K为β-1b,242 K为β-1a).
激素转变为二次元的激活能被确定为β-1b的8.3 kcal mol-1和β-1a的19.6 kcal mol-1.

结论:

结构上的差异,特别是 π 堆中交叉支的程度,决定了二极体的压缩性和压力诱导的解离行为.
光化学解离是一种可行的途径,可以从这些二次体中产生基因对.
模态和基态之间的基态相互转换是禁止对称的,而光化学转换是允许对称的,这是DFT和CAS-SCF计算所支持的.

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