# Electronic structure and magneto-structural correlation study of Cu2UL

Inorganic complexes made of actinide elements are attracting interest, both from experimental and theoretical sides, due to their many potential applications in catalysis, magnetic cooling materials, and notably as high spin molecules, which could behave as single-molecule magnets. Understanding the exchange interactions in polynuclear 3d-5f complexes is essential to the development of new models rationalizing the electronic structure and magnetic properties. In a recent study, the authors report on magnetic properties of trinuclear Schiff base complexes LiMAnMLi (MII = Zn, Cu; AnIV = Th, U; Li = Schiff base; i = 1-4,6,7,9), exhibiting the [M(µ-O)2]2U core structure, featuring 3d-5f-3d subsystems with magnetic Cu(3d9)—U(5f2) interactions. These large inorganic complexes have been investigated theoretically using ADF and relativistic ZORA/B3LYP computations combined with the broken symmetry approach. The calculated coupling constants JCuU between the Cu and U atoms, agree with the observed shift from the M—U antiferromagnetic (AF) character of the L complexes to the ferromagnetic (Ferro) of the L ones. The structural parameters, i.e. the Cu—U distances and the Cu-O-U angles, as well as the electronic factors driving the magnetic couplings are discussed.