Dual-Scandium-Capped Boron Cage: Structural and Electronic Properties of B₁₀Sc₂

Boron clusters exhibit a remarkable propensity to adopt planar or quasi-planar geometries owing to their electron-deficient nature and extensive multicenter bonding. Doping with heteroatoms, particularly transition metals, offers a powerful strategy to redirect these structural preferences and stabilize novel three-dimensional architectures. Herein, we present a comprehensive computational investigation of the geometric structure, electronic properties, and chemical bonding of the binary discandium-doped boron cluster of B₁₀Sc₂. In stark contrast to the planar bare B₁₀ cluster, the B₁₀Sc₂ global minimum can be described as an elongated boron cage composed of ten boron atoms, with two scandium atoms symmetrically anchored at opposite ends. Chemical bonding analysis reveals a sophisticated bonding manifold characterized by dual 10π/6σ aromaticity, wherein a globally delocalized π dectet and a σ sextet cooperatively stabilize the cage framework. Notably, the scandium d orbitals actively participate in the delocalized π system, contributing approximately one electron to the aromatic network. This study elucidates the critical role of scandium in stabilizing an unprecedented boron cage skeleton and establishing dual aromatic character, offering new theoretical insights into the structure-bonding relationships in transition-metal-doped boron clusters.