Metal Encapsulation Engineered Aromaticity Modulation: Transforming Cyclo[16]Carbon From Dual Antiaromaticity to
Long-Yu Cao1, Yan-Zi Yu1, Shi-Jun Wang1
1School of Chemistry and Chemical Engineering, Shandong University, Jinan, China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 12, 2025
Summary
Encapsulating cyclo[16]carbon (C16) with lanthanides or actinides stabilizes the ring. This metal encapsulation tunes aromaticity, offering insights into f-block metal interactions with carbon nanomaterials.
Area of Science:
- Computational Chemistry
- Materials Science
- Nanotechnology
Background:
- Cyclo[16]carbon (C16) exhibits inherent instability due to dual antiaromatic 4n π-electron systems.
- Metal encapsulation is explored as a strategy to stabilize and modify the electronic properties of C16.
Purpose of the Study:
- To investigate the effect of light lanthanide (La-Nd) and actinide (Th-Np) metal encapsulation on the aromaticity of C16.
- To understand the relationship between metal reducibility and induced aromatic character in C16.
Main Methods:
- Computational analyses including topological, natural population, interaction region indicator (IRI), and spin density assessments.
- Frontier molecular orbital and magnetically induced current analyses were employed.
Main Results:
- Metal encapsulation transforms C16's dual antiaromaticity into tunable aromatic or conflicting aromatic states.
- Light actinides (Th-Np) induce dual aromaticity via uniform electron delocalization and bond equalization.
- Lanthanides (La-Nd) induce conflicting aromaticity, with trends correlating to metal reducibility.
Conclusions:
- Metal encapsulation provides a paradigm for precise aromaticity engineering in carbon nanorings.
- This approach offers pathways for developing tailored quantum materials and single-molecule electronics.
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