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Title: Spherical trihedral metallo-borospherenes

The discovery of borospherenes unveiled the capacity of boron to form fullerene-like cage structures. While fullerenes are known to entrap metal atoms to form endohedral metallofullerenes, few metal atoms have been observed to be part of the fullerene cages. Here we report the observation of a class of remarkable metallo-borospherenes, where metal atoms are integral parts of the cage surface. We have produced La3B18and Tb3B18and probed their structures and bonding using photoelectron spectroscopy and theoretical calculations. Global minimum searches revealed that the most stable structures of Ln3B18are hollow cages withD3hsymmetry. The B18-framework in the Ln3B18cages can be viewed as consisting of two triangular B6motifs connected by three B2units, forming three shared B10rings which are coordinated to the three Ln atoms on the cage surface. These metallo-borospherenes represent a new class of unusual geometry that has not been observed in chemistry heretofore.

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Nature Publishing Group
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Journal Name:
Nature Communications
Medium: X
Sponsoring Org:
National Science Foundation
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