“…Besides the lone‐pair electrons, π‐electrons in aromatic or unsaturated molecules and the single electron in radicals are also taken as Lewis bases in triel bonding. When BX 3 (X = F, Cl, Br and I) compounds bind with π‐systems including ethene, 1,2‐difluoroethene and perfluoroethene, lone pair–π, halogen and triel bonding interactions are established, but triel bonding is the most favorable among the three types of interactions . Similarly, BH 2 X (X = F, Cl, Br and I) can participate in hydrogen, halogen and triel bonds in its homodimeric systems owing to its dual σ‐ and π‐hole nature .…”