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Updated: Jun 26, 2026
13:21
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Published on: July 21, 2011
Enhancing the quantum yield of lanthanide clusters via single-site ligand modulation
Tingting Li1, Yaoqin Wu1, Feng Jiang2
1College of Materials Science and Engineering, Jilin Jianzhu University, Changchun, 130012, China.
Nanoscale
|June 25, 2026
Summary
Researchers precisely regulated the local symmetry of europium (Eu3+) clusters using ligand engineering. This atomic-level control significantly enhanced photoluminescence quantum yield in novel luminescent materials.
Area of Science:
- Materials Science
- Inorganic Chemistry
- Nanotechnology
Background:
- Trivalent lanthanide ion (Ln3+) optical properties are limited by lattice site restrictions.
- Controlling Ln3+ lattice sites and coordination environments at the atomic scale remains challenging.
- Atomic precision offers a pathway to overcome these limitations.
Purpose of the Study:
- To develop a ligand engineering strategy for precise regulation of local coordination symmetry in lanthanide clusters.
- To investigate the impact of ligand modification on the optical properties of Eu4Ti9 clusters.
- To establish a quantitative structure-activity relationship for luminescence enhancement.
Main Methods:
- Synthesis of atomically precise Eu4Ti9 clusters protected by 4-trifluoromethyl benzoic acid (4-TFMBA).
- Ligand exchange at the Eu2 site using triphenylphosphine oxide (TPPO) to alter local coordination symmetry.
- Characterization using crystallographic analysis, Judd-Ofelt theory, and temperature-dependent spectroscopy.
Main Results:
- A Eu4Ti9 cluster with Eu3+ ions in distinct coordination configurations (Eu1: D4d, Eu2: D2d) was synthesized.
- Replacing a water ligand with TPPO at the Eu2 site reduced local symmetry and increased photoluminescence quantum yield from 11.32% to 28.94%.
- A clear structure-activity relationship between local symmetry, crystal field parameters, and luminescence enhancement was established.
Conclusions:
- Ligand engineering at the unit site enables precise control over local coordination symmetry in lanthanide clusters.
- This strategy offers a new method for tuning luminescence dynamics in lanthanide materials at the atomic level.
- The findings are significant for the development of advanced lanthanide-based luminescent materials.
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