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Updated: Jul 11, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Synthesis, structure and optical properties of rare-earth benzene carboxylates
Partha Mahata1, K V Ramya, Srinivasan Natarajan
1Framework Solids Laboratory, Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560 012, India.
Dalton Transactions (Cambridge, England : 2003)
|September 11, 2007
Summary
New rare-earth isophthalates were synthesized under mild hydrothermal conditions. These materials exhibit unique two-dimensional structures and luminescence properties, including ligand-sensitized emission and up-conversion.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Crystallography
Background:
- Rare-earth metal-organic frameworks (MOFs) are of interest due to their diverse structures and potential applications.
- Isophthalic acid is a versatile organic linker for constructing MOFs.
- Hydrothermal synthesis offers a controlled method for MOF preparation.
Purpose of the Study:
- To synthesize and characterize novel rare-earth isophthalates.
- To investigate the structural diversity of these compounds.
- To explore their luminescent properties.
Main Methods:
- Hydrothermal synthesis of rare-earth isophthalates using lanthanide salts and isophthalic acid.
- X-ray crystallography to determine the two-dimensional structures.
- Luminescence spectroscopy to analyze emission properties.
Main Results:
- Two series of rare-earth isophthalates with general formulas [M(2)(H(2)O)][{C(6)H(4)(COO)(2)}(2){C(6)H(4)(COOH)(COO)}(2)].H(2)O and [M(2)(H(2)O)(2)][{C(6)H(4)(COO)(2)}(3)].H(2)O were successfully synthesized.
- Distinct two-dimensional structures were formed, stabilized by hydrogen bonding and pi-interactions.
- Partial substitution with Eu and Tb resulted in characteristic red/pink or green luminescence, indicating ligand-sensitized emission.
- The Nd compound displayed UV and blue emission via an up-conversion process.
Conclusions:
- The study successfully synthesized and characterized new rare-earth isophthalates with unique 2D structures.
- The synthesized compounds exhibit interesting luminescence properties, including ligand-sensitized emission and up-conversion.
- These findings contribute to the understanding of rare-earth MOFs and their potential applications in luminescence.
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