Simultaneous Occurrence of Quadruple Lewis Acid–Base Interactions between Selenium Atoms in Selenocarbonyl Dimers

High‐level quantum chemical calculations are performed to investigate C=Se ⋅⋅⋅ Se=C interactions. Bounded structures are found with binding energies between −4 and −7 kJ mol −1 . An energy decomposition analysis shows that dispersion is the more attractive term, and in all cases save one, the electrostatic interaction is attractive despite each selenium atom having a positive σ‐hole at the extension of the C=Se bond. The topological analysis of the molecular electrostatic potential and L ( r )=−∇ 2 ρ ( r ) function, and natural bond orbital analysis reveal that these particular Se ⋅⋅⋅ Se contacts can be considered to be quadruple Lewis acid–base interactions.