IUPAC Recommendations: (Un)equivocal Understanding of Hydrogen and Halogen Bonds and Their (Un)equivocal Naming!

This manuscript shows that Si-H hydrogen acts as a donor of electron density to halogen atoms in Me3Si-H···Y complexes (Y = CF3I, BrCN), thus proving that, consistent with IUPAC definitions of hydrogen and halogen bonds, hydridic hydrogen functions as a halogen bond acceptor. This has been necessitated by a paper recently published asking whether the definition of hydrogen bonding should be revised to include hydridic H atoms acting as electron donors. We discuss the various nomenclatures used for referring to intermolecular/noncovalent bonds formed by various elements and point out the convention established in naming them by IUPAC, after long deliberations among the chemists from all over the world.