Aromaticity of heptafulvene charge transfer complexes with lithium and caesium atoms: A computational approach

► We model stable complexes of lithium and caesium atoms with the heptafulvene molecule. ► Almost 1e of charge is transferred from the metal atom into the heptafulvene ring. ► HOMA index shows substantial bond equalization of the ring. ► The dissociation energy of the caesium complex is much lower. ► EDA reveals more covalent character of the lithium complex.