Several modeling strategies to represent interactions between metal ions and ligands have been proposed. Bonded models can be used to represent the interactions as permanently covalent bonds between the central metal ions and ligand atoms; specifically, these interactions are treated as bond stretching, bending, and torsional motions. Although bonded models can be used to rationalize the building of a rigid metal complex in a solvent, their use of artificially directionally oriented interactions is questionable for the simulation of the vibrational properties of a complex. The connections between coordinated atoms are better represented only in terms of non-bonded interactions. In other words, the Coulomb and van der Waals (vdW) interactions of components neighboring the central metal ions should be taken into account. Generally, the apparent charge of the central atom is set to compensate the charge neutrality of the system; for example, if the charge of one DBM is -1, then the apparent charge of the lanthanide ion in this study must be +3. However, the formal charge of a lanthanide ion is generally less than +3 due to charge transfer to surrounding atoms, as revealed by ab initio calculations. Polarizable force fields have also been developed to simulate metal-organic compounds with small ligand molecules and free lanthanide cations in a solvent. These polarizable models can probably accurately describe Coulombic and dipole interactions; however, the computational and development costs of these force fields may be high because of the difficulty of representing the dipole interactions. For quick and easy development of force fields for CMD, this drawback should thus be avoided. In addition, common CMD software packages such as the Large Scale Atomic/Molecular Massive Parallel Simulator (LAMMPS) 31 do not include all the various polarizable models.