Association between a Lewis-acidic halogen atom in a molecular entity and a Lewis-basic region in another, or the same, molecular entity, which acts as an electron-pair donor, such that the balance of forces of attraction and repulsion results in net stabilization.
Notes: - Typical halogen-bond donors are \(\ce{I2}\), \(\ce{Br2}\), \(\ce{ICN}\), and \(\ce{IC#CH}\).
- This is analogous to a hydrogen bond, in which the \(\ce{H}\) is the acidic atom.
- The interaction provides a stabilization of a few \(\pu{kJ mol-1}\).
Source:
PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 427 (https://doi.org/10.1515/pac-2018-1010)