We report a global planar star-like cluster B3 Li3 featuring three planar tetracoordinate boron centres with a rare spin avoided σ-σ diradical character. The cluster was found to be stable towards dissociation into different fragments. The spin density was found to be localized solely on the three boron atoms in the molecular plane. This spin avoided σ-σ diradical character leads to the extension of the coordination number to yield a neutral B3 Li3 H3 and a cationic B3 Li3 H3 + cluster with three planar pentacoordinate boron centres in their global minimum structures. The planar geometry of the aninonic B3 Li3 H3 - cluster is slightly higher in energy. The planar global clusters were found to maintain planarity in their ligand protected benzene bound complexes, B3 Li3 (Bz)3 , B3 Li3 H3 (Bz)3 and B3 Li3 H3 (Bz)3 + with high ligand dissociation energies offering candidature for experimental detection.
Keywords: Boron; NICS; cluster; hypercoordinated; sigma diradical.
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