Core-Shell Syngenetic σ-Aromaticity in the Crystalline Tri-thorium Cluster: The Pitfalls of a Theoretical Model

It has recently been demonstrated that high symmetry and unusual thermodynamic stability of the famous crystalline tri-thorium cluster isolated by Boronski et al. is determined by the unique charge-shift bonding pattern (ThCl2)3 rather than the σ-aromatic Th3 bonding. However, in the most recently published work by Lin and Mo it has been argued that the experimentally observed charge delocalization in the Th3 core is stabilizing, and hence the isolated complex should be classified as σ-aromatic. In the following we demonstrate that this interpretation cannot be regarded accurate due to high exaggeration of charge delocalization in the theoretical models used by the authors, and we reaffirm our previous prediction of nonaromatic character of the tri-thorium σ-bonding in the isolated crystalline cluster.