With the concept of super-atom, first principles calculations propose a new type of super stable cage clusters AlnH3n that are much more energetic stable than the well established clusters, AlnHn+2. In the new clusters, the aluminum core-frame acts as a super-atom with n vertexes and 2n Al-Al edges, which allow to adsorb n hydrogen atoms at the top-site and 2n at the bridge-site. Using Al12H36 as the basic unit, stable chain structures, (Al12H36)m, have been constructed following the same connection mechanism as for (AlH3)n linear polymeric structures. Apart from high hydrogen percentage per molecule, calculations have shown that these new clusters possess large heat of formation values and their combustion heat is about 4.8 times of the methane, making them a promising high energy density material.

The achievement of the rule‐breaking planar hypercoordinate motifs (carbon and other elements) is mainly attributed to a practical electronic stabilization mechanism, where the bonding of the central atom pz π electrons is a crucial issue. We have demonstrated that strong multiple bonds between the central atom and partial ligands can be an effective approach to explore stable planar hypercoordinate species. A set of planar tetra‐, penta‐ and hexa‐coordinate silicon clusters were herein found to be the lowest‐energy structure, which can be viewed as decorating SiO3 by alkali metals in the MSiO3−, M2SiO3 and M3SiO3+ (M=Li, Na) clusters. The strong charge transfer from M atoms to SiO3 effectively results in [M]+SiO32−, [M2]2+SiO32− and [M3]3+SiO32− salt complexes, where the Si−O multiple bonding and structural integrity of the Benz‐like SiO3 framework is maintained better than the corresponding SiO32− motifs. The bonding between M atoms and SiO3 motif is best described as M+ forming a few dative interactions by employing its vacant s, p, and high‐lying d orbitals. These considerable M←SiO3 interactions and Si−O multiple bonding give rise to the highly stable planar hypercoordinate silicon clusters.