Introduction to Interatomic Potentials/Forcefields

Interatomic potentials (or forcefields) for detailed structures are produced by fitting certain functions within constraints of investigational data or with planned data from the first-principles methods. The experimental data employed for fitting comprises equilibrium lattice parameter, bulk modulus, cohesive energy, thermal expansion coefficient, dielectric constants, elastic modulus, vibration spectrum, surface energy and vacancy formation energies. All these empirical potentials are specifically for their own domain or system. It should be ensured that it is transferable and one must be cautious about applying one specific potential to other systems or situations.