Electronic Hybridization\nbetween Closed-Shell Materials

Closed-shell structures (noble-gas atoms, nonpolar molecules,\nand\n2D layered materials) gathered together with an equilibrium distance\nunder the balanced forces of van der Waals attraction (London dispersion\nforce) and repulsive electronic interaction (REI). Different terminologies\nare used in describing the REI in different systems, such as the Pauli\nrepulsion between noble-gas atoms, the repulsive π–π\nstacking between parallel benzene rings, and the interlayer quasi-bonding\n(QB) between 2D layered materials such as MoS<sub>2</sub>. In the\ncurrent work, based on density functional theory calculations and\nexplicit accounting for the overlap integral between closed-shell\nstructures in our analysis, we show that the REIs in different systems\nhave the same nature; namely, all can be seen as the QB of the two-orbital–four-electron\nrepulsion interaction or a generalization of it to multiple energy-level\ninteractions. All of the REIs cause asymmetric energy-level splitting\nand electron-density depletion at the middle region of the quasi-bond\ndue to the occupation of the antibonding state; however, the degree\nof charge density change and energy-level asymmetry is different.\nOur consistent understanding deepens the connotation of QB interaction\nthat is widely present in van der Waals materials of different and\nmixed dimensions, and hence, our insights inspire further studies\non the electronic hybridization in these materials and exploring its\neffects on diverse properties and applications.