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Perfect in-Plane [5555] Metallo-Annulene Frameworks and Nonmetallo-Annulene Complexes: A Theoretical Prediction
Qin-Wei Zhang1, Qiang Chen1, Xiao-Ni Zhao1
1Institute of Molecular Science, Shanxi University, Taiyuan, China.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|July 1, 2026
Summary
This study predicts novel 2D and 3D metallo- and nonmetallo-annulene frameworks with planar tetracoordinate centers. These aromatic systems exhibit enhanced stability and potential for new materials discovery.
Area of Science:
- Computational Chemistry
- Materials Science
- Inorganic Chemistry
Background:
- Recent discovery of 3D [55555] metallo-annulene frameworks and proposed 2D [55555] metallo-annulene complexes.
- Inspiration drawn from existing metallo-annulene structures for exploring new chemical spaces.
Purpose of the Study:
- To predict novel perfect in-plane [5555] metallo- and nonmetallo-annulene frameworks.
- To investigate the electronic structure, bonding, and aromaticity of these predicted systems.
- To explore the potential for 2D expansion and 3D nanobelt generation.
Main Methods:
- Extensive first-principles theory calculations.
- Detailed bonding pattern and ring current analyses.
- Computational simulation of NMR, IR, and UV-vis spectra for key species.
Main Results:
- Prediction of perfect in-plane [5555] metallo-annulene frameworks ([Fe]C12H8 and [Co]C12H8+) and nonmetallo-annulene complexes (PC12H8-, SC12H8, ClC12H8+).
- Identification of planar tetracoordinate metal/nonmetal centers participating in delocalized π-bonding, leading to π-aromaticity and enhanced stability.
- Demonstration of potential for 2D enlargement and 3D nanobelt formation from these annulene units.
Conclusions:
- The predicted metallo- and nonmetallo-annulene complexes exhibit significant aromaticity and stability due to planar tetracoordinate centers.
- These novel frameworks offer pathways for designing extended 2D materials and 1D nanostructures.
- Computational spectral data are provided to guide future experimental synthesis and characterization.
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