通过超快速发射光谱学观察到的异构 Cu (I) 复合体的结构变化动态
Masashi Sanga1, Kosuke Nakamura1, Munetaka Iwamura1
1Department of Chemistry, Graduated School of Science and Engineering, University of Toyama, 3190, Gofuku, Toyama-shi, Toyama 930-8555, Japan. miwamura@sci.u-toyama.ac.jp.
Physical chemistry chemical physics : PCCP
|May 31, 2023
概括
复合物中含有2,9-二甲基-1,10-类衍生物和素联体的铜 (I) 复合物在减少二氧化碳方面表现出高效率. 这项研究揭示了超快激发状态的动态,包括内部转换和结构变化,这对于它们的光敏化功能至关重要.
科学领域:
- 光化学和光物理学
- 协调化学 协调化学
- 催化剂是一种催化剂.
背景情况:
- 铜 (I) 复合物是减少二氧化碳的有希望的光敏化剂,可以实现高量子产量.
- 了解兴奋状态动态对于优化光敏剂性能至关重要.
研究的目的:
- 为了研究[Cu{I}{dmp}{P}{2}+复合物的超快兴奋状态动态.
- 阐明内部转换,结构变化和系统间交叉的机制.
- 为了将兴奋状态动态与光敏剂在二氧化碳减排中的效率相关联.
主要方法:
- 五秒光向上转换光谱学.
- 纳米秒时间分辨率的发射光谱学.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 在乙二溶液中激发状态的排放衰变遵循三指数动力学,时间常量为0.040ps,0.78ps和8.0ps.
- 取决于溶剂的0.78ps时间常数归因于激发状态中的结构变化 (约翰-泰勒扭曲).
- 时间常数0.040ps和8.0ps分别分配给S1→S1内部转换和S1→T1系统间交叉.
结论:
- 超快的动态,包括快速的内部转换和结构重组,是这些铜光敏剂效率的关键.
- 激发状态中的Jahn-Teller扭曲显著影响光谱属性和斯托克斯转移.
- 阐明的兴奋状态通路为设计改进的光敏剂提供了洞察力,用于二氧化碳的催化降解.
相关概念视频
03:02Colors and Magnetism
12.0K
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...
12.0K
02:58Crystal Field Theory - Octahedral Complexes
26.9K
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...
26.9K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.9K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.9K
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
1.6K
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this...
1.6K
01:32UV–Vis Spectroscopy of Conjugated Systems
7.1K
Organic compounds with conjugated double bonds show strong absorption features in the UV–visible region of the electromagnetic spectrum attributed to π → π* electronic excitations. Generally, a UV–vis absorption spectrum is recorded as a plot of absorbance vs wavelength. The wavelength of maximum absorbance, which manifests as a peak in the absorption spectrum, is denoted as λmax.
One of the factors influencing λmax is the extent...
One of the factors influencing λmax is the extent...
7.1K
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
1.1K
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are...
1.1K