Chirality Enhanced Halogen Bonding Cooperativity and Structural Stability of Two-Dimensional Iodinenes

Halogen bond (XB), as a high-directional noncovalent interaction, is widely found and applied in many areas, such as chemistry, physics, and material science. Recently, XB has been successfully utilized to construct two-dimensional (2D) iodine networks, dubbed iodinenes. However, the behavior of XB in such a single-element and periodic system, which is constructed by XB networks between iodine molecules, as well as the mechanism of stabilizing iodinene, have not been thoroughly investigated. In this work, based on first-principles calculations, we found that structural chirality can increase the cooperativity of XB and preserve the directionality of XB in lattice vibration, leading to the dynamic stability of iodinenes, while the mirror symmetry has the opposite effect on the XB network. These results not only extend our understanding of XB in iodinenes but also provide new insight into studying the relationship between the chirality and stability of XB in periodic systems.