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Published on: April 14, 2020
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New lanthanide-CB[6] coordination compounds: relationships between the crystal structure and luminescent properties
Fausthon F da Silva1, Carlos A F de Oliveira, Eduardo H L Falcão
1Departamento de Química Fundamental, Universidade Federal de Pernambuco, 55067-901, Recife-PE, Brazil. salvesjr@ufpe.br.
Dalton Transactions (Cambridge, England : 2003)
|February 14, 2014
Summary
Four new lanthanide complexes with cucurbit[6]uril (CB[6]) were synthesized. These compounds exhibit unique luminescent properties, including novel transitions for europium and terbium, confirmed by single crystal X-ray diffraction.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Cucurbiturils (CB[n]) are macrocyclic hosts with versatile applications.
- Lanthanide complexes are known for their unique photophysical properties.
Purpose of the Study:
- To synthesize and characterize new lanthanide-cucurbit[6]uril complexes.
- To investigate the luminescent properties of these novel compounds.
Main Methods:
- Single crystal X-ray diffraction for structural determination.
- Spectroscopic analysis (UV-Vis, luminescence) for photophysical characterization.
- Synthesis in acidic aqueous media.
Main Results:
- Four isostructural lanthanide complexes with the formula [Ln2(H2O)12(H2O@CB[6])]Cl6(H2O)4 were obtained.
- Eu(3+), Sm(3+), and Tb(3+) complexes displayed characteristic f-f transitions.
- Novel transitions for Eu(3+) and Tb(3+) within lanthanide-CB[n] systems were observed.
Conclusions:
- The study successfully synthesized and characterized new lanthanide-cucurbit[6]uril complexes.
- The observed luminescent properties are consistent with the determined crystal structures.
- The discovery of new transitions expands the understanding of lanthanide-CB[n] interactions.
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