 The potential for models such as TIP3P (transferable intermolecular potential with 3 points) and TIP4P is represented by

where "kC", the electrostatic constant, has a value of 332.1 Å·kcal/(mol·e²) in the units commonly used in molecular modeling; "qi" and "qj" are the partial charges relative to the charge of the electron; "rij" is the distance between two atoms or charged sites; and "A" and "B" are the Lennard-Jones parameters.The charged sites may be on the atoms or on dummy sites (such as lone pairs).In most water models, the Lennard-Jones term applies only to the interaction between the oxygen atoms.