Binding of noble gas atoms by superhalogens

Because of their closed shells, noble gas (Ng) atoms (Ng = Ne, Ar, Kr, and Xe) seldom take part in chemical reactions, yet finding such mechanisms not only is of scientific interest but also has practical significance. Following a recent work by Mayer et al. [Proc. Natl. Acad. Sci. U. S. A. 116, 8167-8172 (2019)] on the room temperature binding of Ar to a superelectrophilic boron site embedded in a negative ion complex, B-12(CN)(11)(-), we have systematically studied the effect of cluster size and terminal ligands on the interaction of Ng by focusing on B12X11(Ng) (X = H, CN, and BO) and B12X10(Ng)(2) (X = CN and BO) whose stabilities are governed by the Wade-Mingos rule and on C5BX5(Ng) (X = H, F, and CN) and C4B2(CN)(4)(Ng)(2) whose stabilities are governed by the Huckel's aromaticity rule. Our conclusion, based on density functional theory, is that both the cluster size and the terminal ligands matter-the interaction between the cluster and the Ng atoms becomes stronger with increasing cluster size and the electron affinity of the terminal ligands. Our studies also led to a counter-intuitive finding-removing multiple terminal ligands can enable electrophilic centers to bind multiple Ng atoms simultaneously without compromising their binding strength.

Automated summary

Noble gas atoms typically do not participate in chemical reactions, but research has shown that their interactions with specific substances vary depending on cluster size and terminal ligands. The study concludes that the interaction with noble gas atoms becomes stronger with increasing cluster size and the electron affinity of the terminal ligands, and also reveals a counter-intuitive finding.