客人诱导的孔腔呼吸控制了在化桥架框架中的旋转状态
Michał Magott1,2, Klaudia Płonka1, Barbara Sieklucka1
1Faculty of Chemistry, Jagiellonian University Gronostajowa 2 30-387 Kraków Poland michal.magott@uj.edu.pl dawid.pinkowicz@uj.edu.pl.
Chemical science
|September 22, 2023
概括
这项研究表明,客分子如何调整多孔协调聚合物的自旋状态. 通过吸附二氧化碳,材料可以吸收二氧化碳.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 铁 (II) 旋转交叉 (SCO) 化合物表现出低旋转 (LS) 和高旋转 (HS) 状态之间的过渡,加上体积变化.
- 调节晶格容量后合成提供了一个调整SCO行为的途径,可能会逆转过渡.
- 多孔协调聚合物 (PCP) 提供了动态框架,其中客主互动可以诱导结构变化.
研究的目的:
- 通过调节其体积与客分子来证明呼吸的化物桥接PCP中的自旋状态调节.
- 综合和描述一个新的3D协调框架,展示SCO和弹性丧.
- 调查客体吸附和光交换对PCP的旋转状态和结构性质的影响.
主要方法:
- 一个3D化物桥接协调框架的合成{[FeII{4-CNpy) ]2[WIV{CN) ]8·4H2O} (1·4H2O).
- 从单晶转化为单晶,通过溶解转化为无孔的形式 (1),从而诱导体积的减少.
- 吸附二氧化碳进入无孔框架 (1) 形成 (1·4CO2),导致体积增加.
- 可变温度磁感应度测量以研究SCO行为.
- 低温光交换实验以探测框架弹性.
主要成果:
- 合成的框架1·4H2O显示了一个广泛的,逐渐的SCO过渡,由于弹性挫折而引起的歇斯底里.
- 将1·4H2O激活到1的结果是体积减少7.3%,并在93K时产生急剧的非歇斯底里性SCO.
- 光交换实验揭示了框架的弹性,在辐射时1转换为转移稳定的HS状态.
- 将二氧化碳吸附到1中会产生1·4CO2,增加15%的体积,并将HS状态稳定到2K.
- 客人引起的体积变化直接影响和调整SCO-PCP的旋转状态.
结论:
- 客人诱导的结构调制,特别是体积变化,提供了一种有效的方法来调整呼吸PCP中的旋转交叉行为.
- 使用常见气体演示的合成后客户交换提供了一种多功能方法来控制SCO属性.
- 这项工作突出了动态协调框架的潜力,用于开发可调节自旋状态的可切换材料.
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