相关实验视频
Updated: Jul 7, 2026
09:26
Synthesis and Characterization of Supramolecular Colloids
Published on: April 22, 2016
在4-octadecyloxystilbazolium arylcarboxylate膜中的单层和双层堆叠对齐之间,可逆光驱动的结构变化
Osamu Ohtani1, Hiroki Kato, Tatsuto Yui
1Department of Crystalline Materials Science, School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan.
Journal of the American Chemical Society
|November 20, 2003
概括
暴露于光线会触发N-甲基-4-八度环氧化烯酸膜的可逆结构变化. 这些薄膜膨胀和收缩,展示了潜在应用的可控形态变化.
科学领域:
- 材料科学 材料科学 材料科学
- 摄影化学的使用.
- 超分子化学 超分子化学
背景情况:
- 由N-甲基-4-octadecyloxystilbazolium基碳酸盐 (C18OStz+X-) 组成的多层膜具有独特的特性.
- 了解光引起的形态变化对于开发先进材料至关重要.
研究的目的:
- 为了研究C18OStz+X-.的多层膜中的光驱动形态变化.
- 阐明观察到的结构变化及其可逆性的背后机制.
主要方法:
- 进行X射线衍射 (XRD) 分析,研究沿c轴的结构变化.
- 替代紫外线照明 (>350nm和254nm) 诱导和逆转结构变化.
- 扫描电子显微镜 (SEM) 和光显微镜用于分析表面图案.
主要成果:
- 在不同的紫外线波长下,在c轴上堆叠的薄膜的光刺激膨胀和收缩被观察到.
- 薄膜中的单层和双层单元之间的可逆转换驱动了叶片变化.
- 结构调整,包括从单层转化为两层的转化,是通过光环二氧化部分的光环二氧化开始的,即使在低循环二氧化形成 (10%) 时也是如此.
结论:
- 光照射可以可控地改变C18OStz+X-多层膜的形态.
- 由光环二极化驱动的结构变化的可逆性为光响应材料提供了潜力.
- 在薄膜表面上成功演示了光诱导的图案,突出了在表面工程中的潜在应用.
相关概念视频
02:42Ionic Crystal Structures
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
02:52Stereoisomerism
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...
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
02:33Stereoisomerism of Cyclic Compounds
In this lesson, we delve into the role of ring conformation and its stability, which determines the spatial arrangement and, consequently, the molecular symmetry and stereoisomerism of cyclic compounds. 1,2-Dimethylcyclohexane is used as a case study to evaluate the possible number of stereoisomers. Here, given the multiple (n = 2) chiral centers, there are 2n = 4 possible configurations that lack a plane of symmetry, as the ring skeleton exists in a non-planar chair conformation. In addition,...
01:26Photochemical Electrocyclic Reactions: Stereochemistry
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
01:30The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...