The scandium doped boron cluster B27Sc2+: a fruit can-like structure
A systematic exploration of the potential energy surface through evolutionary search algorithms was carried out to identify the most stable B27Sc2+ structure. A nearly perfect boron box was found featuring a triple ring tubular shape with high D9h symmetry formed by three B9 strings connected with each other and the box is capped by an Sc–Sc dimer. Each Sc atom is placed at the centre of a B9 terminal string along the C9 axis. The shapes of the MOs of the B27+ triple ring are reproduced by eigenstates of a simple model of a particle on a hollow cylinder (HCM). The resulting MOs demonstrate that only the set of radial-MOs of the B27+ skeleton significantly interact with MOs of a stretched Sc2 dimer. This structure is representative of a new fruit can-type of shape in the family of doped boron clusters.