Decorating Zintl polyanions with alkali metal cations: A novel strategy to design superatom cations with low electron affinity

摘要

AbstractThe possibility to design new superatom species by decorating Zintl polyanions with alkali metal cations has been examined under density functional theory in this work. Utilizing typical Zintl ions as examples, MLin+1+cations have been constructed and investigated in detail. Calculations show that all of the Zintl anions Mn?preserve their geometric and electronic integrity in the global minima of MLin+1+cations. The stability of these studied cations is guaranteed by the strong ionic bonds between the Zintl core and ligands, as well as their large HOMO?LUMO gaps and positive dissociation energies with respect to the loss of a Li+cation. In particular, all these proposed cations possess pretty low vertical electron affinities, verifying their superalkali or pseudoalkali identities. Besides, the feasibility of using these proposed MLin+1+cations as building blocks to design new superatom compounds is explored by theoretically constructing and charactering two series of MLin+1?(super)halogen compounds. We, therefore, hope that this work will not only provide an approach to obtain new superatoms by utilizing various Zintl polyanions as the central cores, but also offer new building blocks for cluster-assembled nanomaterials in which exceptionally strong reducing matters are required.Graphical abstractDisplay OmittedHighlights?Novel superatom species are achieved by decorating Zintl polyanion with alkali metal cations.?Zintl polyanions retain their geometric and electronic integrity inside the lowest-energy MLin+1+cations.?These proposed cations are stable in view of their large HOMO–LUMO gaps and positive dissociation energies.?It is feasible to utilize the MLin+1+cations as building blocks to synthesize stable superatom compounds.]]>