在金属-有机框架中超辐射和方向刺激迁移
Sreehari Surendran Rajasree1, Jierui Yu1, Saied Md Pratik2
1Department of Chemistry and Biochemistry, Southern Illinois University, 1245 Lincoln Drive, Carbondale, Illinois 62901, United States.
Journal of the American Chemical Society
|January 14, 2022
概括
金属有机框架 (MOF) 模仿光收获复合体,由于多连接器激子而表现出超辐射. 在MOF中,刺激子的大小和动态与连接器对称性有关,指导太阳能转换系统的设计.
科学领域:
- 材料科学
- 摄影化学
- 纳米技术
背景情况:
- 晶体金属有机框架 (MOF) 作为天然光合成光采集复合体 (LHC) 的合成类型.
- 在MOF中有机染色体 (链接体) 的排列导致独特的光物理性质,包括称为分子激子的空间分散激发状态.
- 这些多连接器激子表现出超辐射,这是LHC合振荡器的特征,辐射速率常数超过单个连接器.
研究的目的:
- 研究MOF中的链接电子对称性和分子激子大小之间的关系.
- 开发一个理论模型来预测MOF中的激子动态和能量转移速度.
- 建立基于MOF的太阳能转换系统的设计原则.
主要方法:
- 三种MOF (PCN-222(Zn,NU-1000,SIU-100) 具有不同的链接器但具有相似的拓的实验性表征.
- 开发和应用一个理论的多连接激励模型.
- 测量和预测激子跳跃时间和异质性.
主要成果:
- MOF中的分子激子的大小取决于有机链接器的电子对称性.
- 理论模型准确地预测了能量传输速率常数和激励子跳跃时间,从皮秒到数百皮秒.
- 刺激物位移表现出异构性,沿着晶体学c轴进行偏向迁移.
结论:
- 这项研究阐明了MOF组装链接器中控制激子大小和动态的因素.
- 这些发现为优化基于MOF的太阳能转换系统提供了关键的设计原则.
- 了解激子的行为是定位元件的关键,
更多相关视频
06:53Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
2.2K
07:14Author Spotlight: Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
3.2K
相关概念视频
02:58Crystal Field Theory - Octahedral Complexes
28.2K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
28.2K
03:02Colors and Magnetism
12.5K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
12.5K
02:42Valence Bond Theory
9.8K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.8K