Computational approaches to the study of chalcogen bonding interactions

The chalcogen bond (ChB) is acknowledged as a significant noncovalent interaction that occurs between an electron-deficient chalcogen atom (donor) and a Lewis base (acceptor). The deep understanding of this interaction remains a subject of debate, with interpretations ranging from a charge-transfer (CT) model, which suggests a polarized covalent character, to the so-called σ-hole model, which implies a predominantly electrostatic interaction. Over the past decades, various computational approaches and theoretical models have been employed to elucidate the nature of ChBs, often aiming at quantifying the different contributions - such as orbital, electrostatic, and dispersion forces - to the overall interaction energy. In this review, we present a comparative analysis of the computational approaches used to describe chalcogen bonding interactions, their consistency with experimental evidence, and an overview of the model systems investigated.