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Updated: Mar 29, 2026
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Fabrication of Three-Dimensional Graphene-Based Polyhedrons via Origami-Like Self-Folding
Published on: September 23, 2018
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Predicting experimentally stable allotropes: Instability of penta-graphene
Christopher P Ewels1, Xavier Rocquefelte2, Harold W Kroto3
1Institut des Matériaux Jean Rouxel, CNRS UMR 6502, Université de Nantes, 44322 Nantes, France; chris.ewels@cnrs-imn.fr kroto@chem.fsu.edu.
Summary
Researchers evaluated criteria for experimentally viable theoretical carbon allotropes. They dispute claims of stability and experimental relevance for penta-graphene and Haeckelites.
Area of Science:
- Materials Science
- Chemistry
- Physics
Background:
- Numerous theoretical carbon allotropes have been proposed but not experimentally realized.
- Experimental viability criteria for novel carbon phases are crucial for scientific progress.
Purpose of the Study:
- To discuss essential criteria for the experimental viability of theoretical carbon allotropes.
- To critically evaluate the proposed stability and experimental relevance of Haeckelites and penta-graphene.
Main Methods:
- Theoretical analysis of proposed carbon allotrope structures.
- Evaluation of structural and energetic criteria for experimental synthesis.
- Comparative assessment of Haeckelites and penta-graphene against established viability criteria.
Main Results:
- Haeckelites, 2D networks of sp(2)-carbon with pentagons and heptagons, were examined.
- Penta-graphene, a pentagonal layer with mixed sp(2)- and sp(3)-coordinated carbon, was analyzed.
- The study disputes claims regarding the potential stability and experimental relevance of penta-graphene.
Conclusions:
- Establishing clear criteria is vital for identifying promising theoretical carbon allotropes.
- Not all theoretically proposed carbon structures, like penta-graphene, may meet the requirements for experimental realization.
- Further rigorous evaluation is needed for novel carbon allotrope candidates.
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