![Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F61682.jpg&w=3840&q=50)
Novel supramolecular assemblies based on coordination of samarium cation to cucurbit[5]uril
Kai Chen1, Li-Li Liang, Yun-Qian Zhang
1Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, People's Republic of China.
Inorganic Chemistry
|July 19, 2011
Summary
Samarium and cucurbit[5]uril systems form diverse supramolecular structures. The addition of hydroquinone, nickel, or copper ions dictates the assembly, creating polymers, chains, frameworks, and netting sheets.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Cucurbit[5]uril (Q[5]) molecules are macrocyclic hosts with unique cavity structures.
- Samarium (Sm) cations can interact with organic molecules to form coordination complexes.
Purpose of the Study:
- To investigate the coordination behavior of samarium-Q[5] systems.
- To explore the formation of supramolecular assemblies influenced by a third species.
- To characterize the resulting structures formed with different additives.
Main Methods:
- Coordination chemistry techniques were employed.
- Structural analysis of samarium-Q[5] complexes in the presence of hydroquinone, nickel, and copper ions.
- Characterization of supramolecular assemblies using various analytical methods.
Main Results:
- In the absence of a third species, samarium coordinates with Q[5] to form a molecular bowl.
- In the presence of hydroquinone, a 1D polymer (···Sm-Q[5]-Sm-Q[5]-Sm···) is formed.
- Nickel ions induce the formation of 1D supramolecular chains and hexagonal open frameworks.
- Copper ions lead to the construction of Q[5]-based hexagonal netting sheets.
Conclusions:
- The coordination of samarium-Q[5] systems is highly dependent on the presence and nature of a third species.
- Diverse supramolecular architectures, including polymers, chains, frameworks, and 2D sheets, can be controllably synthesized.
- These findings highlight the versatility of samarium-Q[5] in constructing complex supramolecular materials.
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