The ferrocene-lithium cation complex in the gas phase

The stable isomers of the ferrocene-lithium cation gas-phase ion complex ha ve been studied with the hybrid density functional theory. The method of ca lculation chosen has been tested checking its performance for the more stud ied protonated ferrocene species. Our calculations demonstrate that the pro cedure used is reliable. We have found two isomers of the ferrocene-lithium cation complex separated by a barrier of 25.6 kcal/mol. The most stable is omer of this complex has Li+ on-top of one of the cyclopentadienyls, while in the least stable isomer Lit binds the central iron metal. The latter iso mer has been characterized as a planetary system in the sense that Li+ has one thermally accessible planar orbit around the central ferrocene moiety. Our calculations lead to a value of ferrocene's gas-phase lithium cation ba sicity of 37.4 kcal/mol for the on-top complex and 29.4 kcal/mol for the me tal-bound complex.