Y©B8C4 cluster: a boron–carbon molecular wheel with dodeca-coordination number in plane

Abstract

Computational evidence is reported for the largest planar molecular wheel of the Y©B₈C₄ cluster, featuring an yttrium atom enclosed by a highly symmetric B₈C₄ ring. The B₈C₄ ring is viable in the –(BCB)₄– form with double 9π/10σ aromaticity. The centered yttrium atom is dodeca-coordinated with the peripheral B₈C₄ ring, which sets a record coordination number for a planar structure in chemistry heretofore.