Interaction Nature and Computational Methods for Halogen Bonding: A Perspective.

Halogen bonds are noncovalent interactions that have been widely used in many fields, including drug design, crystal engineering, and material sciences. A clear understanding of the nature of halogen bonding as well as the proper theoretical bonding description, especially the development of efficient and accurate computational chemical methods and their application in complex systems, is of great significance to promote the development of related fields. In this perspective, we reviewed the investigations of the nature of halogen bonding in recent years and discussed the development of quantum mechanical, molecular mechanical, and empirical scoring function methods in properly describing halogen-bonding interactions, as well as their achievements in corresponding areas. An evaluation on the performance of various quantum mechanical and semiempirical quantum mechanical methods in describing halogen bonds was also included, involving the DFT-D4 scheme and the recently reported xTB methods. We hope this perspective may be helpful, from the insights of computational tools and methods, in providing reference and enlightenment for the application of halogen bonds in fields like high-throughput virtual screening and rational drug design.