Research Highlights

• Subject Category:
  • Materials

Published online: 24 September 2008 | doi:10.1038/nchina.2008.221

Fullerenes: Symmetry breakers

Felix Cheung

Introduction

© (2008) Nature Materials

Buckminsterfullerene (C₆₀) was discovered more than two decades ago. However, icosahedrally symmetric C₆₀ (I_h-C₆₀), which resembles a soccer ball, remains the only C₆₀ species that can be made in an experiment. Structural variations of C₆₀ — especially those without icosahedral symmetry — might be possible, but nobody has figured out how to make them yet. Suyuan Xie and co-workers at Xiamen University¹ have now produced two chlorinated symmetry-breaking C₆₀ species — just one step away from an actual symmetry-breaking C₆₀ structure.

The carbon atoms of I_h-C₆₀ are arranged in hexagons and pentagons, in which no two pentagons share an edge. Fusing pentagons together would make the C₆₀ structure unstable, so Xie and co-workers overcame this problem by adding chlorine atoms at the edges of the fused pentagons. They managed to produce two symmetry-breaking species, C₆₀Cl₈ and C₆₀Cl₁₂ (pictured), both of which contained fused pentagons in their structure.

When the researchers optimized the reaction conditions, they could improve the yield of the C₆₀Cl₈ to 3.5% the weight of the crude product, which is comparable to the 4.2% yield of I_h-C₆₀. The yield of C₆₀Cl₁₂ is much lower, but still enough for detailed characterization and property investigations in future studies.

The authors of this work are from:
State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.

Reference

1. Tan, Y. Z. et al. Two I_h-symmetry-breaking C₆₀ isomers stabilized by chlorination. Nature Mater. doi: 10.1038/nmat2275 (2008). | Article |