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On the aromaticity of actinide compounds

Nature Reviews Chemistry volume 8, pages 551–560 (2024)Cite this article

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Abstract

The chemistry of actinides has flourished since the late 2010s with the synthesis of new actinide complexes and clusters. On the theoretical side, a range of tools is available for the characterization of these heavy element-containing compounds, but discrepancies in the assessment of aromaticity using different tools have led to controversies. In this Perspective, we examine the origin of controversies relating to the aromaticity of metallic compounds, with a focus on actinides. The aromaticity of actinides is important, not because these molecules are numerous or have a special role in catalysis or reactivity, but because this topic pushes theories of aromaticity to their limits. Owing to its reference independence, the magnetic criterion of aromaticity has been the most popular choice for the characterization of the aromaticity of metallic compounds, including actinide compounds. Through examination of several case studies, we show why this criterion might be misleading for metallic species and explain how findings relating to actinide compounds could reshape theories of aromaticity, not just for actinides but perhaps also for well-known hydrocarbons.

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Fig. 1: Influence of strong local currents on shielding zones.
Fig. 2: Experimentally characterized aromatic actinides.
Fig. 3: Current density pattern of the [{Th(C8H8)Cl2}3K2] model system.
Fig. 4: Analysis of the aromaticity the [{Th(C8H8)Cl2}3K2] model system using electronic and energetic criteria.

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Acknowledgements

C.F.N. thanks the National Science Centre, Poland (grant no. 2020/39/B/ST4/02022) for funding.

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    Zahra Badri & Cina Foroutan-Nejad

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Badri, Z., Foroutan-Nejad, C. On the aromaticity of actinide compounds. Nat Rev Chem 8, 551–560 (2024). https://doi.org/10.1038/s41570-024-00617-y

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