Аннотация:This chapter describes a general theoretical approach that considers a point charge approximation to calculating the energy spectrum and the wave function of the low-lying magnetic levels of a lanthanide ion submitted to the crystal field (CF) created by the surrounding ligands. With this rough geometrical information, the non-vanishing CF parameters can be estimated and general trends about the most suitable coordination geometries needed to design single-ion magnets (SIMs) can be obtained. Finally, more quantitative information about parameters, levels and magnetic properties can be extracted using an effective description of each donor atom, which takes into account effective charges and metal-ligand distances. With the help of this electrostatic model the chapter draws the key structural and electronic features that are needed to be taken into account in the design of single-molecule magnets (SMMs) and spin qubits based on these mononuclear lanthanide-based complexes.
