捐赠体和受体染色体的非平行堆逃避双质电荷重组
Ajith R Mallia1, P S Salini1, Mahesh Hariharan1
1School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram , CET Campus, Sreekaryam, Thiruvananthapuram, Kerala, India 695016.
Journal of the American Chemical Society
|October 7, 2015
概括
研究人员开发了一种非平行堆叠的供体受体对,以延长光诱导电荷分离状态的寿命. 这种新型结构显著降低了电荷重组,导致材料科学中的长寿命激发状态.
科学领域:
- 材料科学
- 摄影化学
- 超分子化学
背景情况:
- 捐赠者-接受者 (DA) 对光化学过程中的电荷分离至关重要.
- 实现长寿命的电荷分离状态对于太阳能转换和分子电子等应用是必不可少的.
- 立体阻碍可以影响分子几何和包装,影响电子性质.
研究的目的:
- 研究DA对的非平行堆叠安排,以延长光诱导的电荷分离状态.
- 了解固体排斥在分子几何和固体包装中的作用.
- 将分子排列与电荷分离中间体的寿命相关联.
主要方法:
- 纳胺-纳二 (NIN) 的合成
- 在溶液和晶体状态下对二元体的几何特征.
- 用于监测电荷分离状态的Femtosecond暂时吸收光谱.
主要成果:
- 在NIN二中,体排斥会产生非平面几何.
- 非平面几何学促进了DA堆在晶体状态 (三临床空间组) 的非平行排列.
- 光激发导致电子转移,形成基离子对,在聚合状态下与单体状态 (<110 fs) 相比寿命显著长.
结论:
- 非平行DA堆叠安排有效延长光诱导电荷分离状态的寿命.
- 立体效应可以战略性地用于控制分子包装和增强光物理性质.
- 这种方法为在光电子应用中设计具有更高性能的先进材料提供了途径.
更多相关视频
相关概念视频
Stereoisomerism
14.7K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
14.7K
The Antenna Complex
8.7K
Plants and other photosynthetic organisms comprise pigments capable of absorption of direct sunlight. These pigments are present in the reaction center - the main site of photochemical reactions as well as in the antenna complex. Under average light conditions, the rate at which reaction center pigments absorb light is far below the electron transport chain's capacity. As a result, the reaction center alone cannot provide enough energy to drive photosynthesis. The photosynthetic efficiency can...
8.7K
Photochemical Electrocyclic Reactions: Stereochemistry
2.4K
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
2.4K
The Photochemical Reaction Center
5.9K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
5.9K
¹H NMR: Complex Splitting
2.2K
A proton M that is coupled to a proton X results in doublet signals for M. However, NMR-active nuclei can be simultaneously coupled to more than one nonequivalent nucleus. When M is coupled to a second proton A, such as in styrene oxide, each peak in the doublet is split into another doublet.
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
Splitting diagrams or splitting tree diagrams are routinely used to depict such complex couplings. While drawing splitting diagrams, the splitting with the larger coupling constant is usually applied...
2.2K
Colors and Magnetism
14.6K
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...
14.6K


