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Updated: Jan 10, 2026
07:24
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
18.3K
Pressure-Induced Three- to Two-Dimensional Structural Transition in Light Lanthanide Trichlorides
Fenghua Ding1,2, Qian Wang1, Danilo Puggioni3
1School of Metallurgy and Environment, Central South University, Changsha 410083, PR China.
Inorganic Chemistry
|November 24, 2025
Summary
High pressure transforms rare-earth chlorides into 2D layered structures. This synthesis yields novel materials with potential applications in functional van der Waals-type devices.
Area of Science:
- Solid-state chemistry
- Materials science
- Crystallography
Background:
- Rare-earth chlorides commonly form 3D UCl3-type structures with 9-fold lanthanide coordination.
- Understanding structural transitions under pressure is crucial for materials design.
Purpose of the Study:
- To synthesize and characterize high-pressure polymorphs of rare-earth chlorides.
- To investigate the structural changes and coordination number shifts in LnCl3 under high pressure.
Main Methods:
- High-pressure synthesis at 5 GPa and 1000 °C.
- Structural characterization of synthesized materials.
- Density functional theory (DFT) calculations to rationalize observed behavior.
Main Results:
- Rare-earth chlorides (La, Ce, Pr, Nd, Gd, Y) were synthesized in the 2D NdBr3-type structure (Cmcm).
- YCl3 transitions from CN=6 to CN=8 under pressure.
- La-Gd trichlorides exhibit an unexpected CN reduction from 9 to 8, explained by bond shortening and packing density.
Conclusions:
- High pressure stabilizes recoverable 2D polymorphs of rare-earth chlorides.
- This expands the known NdBr3-type structures and offers routes to new functional materials.
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