An inversion procedure to derive coarse-grained ion–ion interaction potentials for lanthanoid chloride solutions is performed. Explicit-solvent molecular dynamics simulations are carried out for two binary salts in aqueous solution, Nd3+Cl−and Dy3+Cl−. The radial distribution functions obtained from simulations are then used to define effective short-range pair potentials. These potentials define an implicit solvent model, corresponding to the original (full atom) system, which represents the ions as charged solvated particles moving in a dielectric medium. Within this new representation, it is possible to obtain accurate estimates for structural and thermodynamic properties that compare favorably to available experimental data.