Intramolecular Nonvalent Interactions in the $${\text{Eu}}_{{\text{2}}}^{{{\text{II}}}}$$EuIII(μ-ORF)2(μ2-ORF)3(μ3-ORF)2(DME)2 Complex

Abstract

A quantum chemical study of fluorinated europium alcoholate $${\text{Eu}}_{{\text{2}}}^{{{\text{II}}}}$$ EuIII(μ-ORF)2(μ2-ORF)3(μ3-ORF)2(DME)2 (I), where DME is 1,2-dimethoxyethane, is performed. The structure of the complex contains numerous F⋅⋅⋅F, F⋅⋅⋅O, F⋅⋅⋅H, and C–F → Eu interactions. The nature and energy of these nonvalent interactions is studied in the framework of R. Bader’s quantum theory “Atoms in Molecules.” Nonvalent interactions between the negatively charged fluorine atoms in the structure of complex I can occur due to the donation of the electron density from the regions where the electron density is fairly highly concentrated to the regions of its relative depletion. Weaker C–F → Eu interactions are observed by the additional study using the Topos Pro structural topological program package. These interactions are confirmed by the study of the delocalization indices of electrons in the region of potential Eu⋅⋅⋅F interactions.