Equivalence of the deformed modified Rosen–Morse potential energy model and the Tietz potential energy model

Abstract

By applying the dissociation energy and the equilibrium bond length for a diatomic molecule as explicit parameters, we generate an improved expression for the deformed modified Rosen–Morse potential energy model. It is found that the deformed modified Rosen–Morse potential model and the well-known Tietz potential model are the same empirical potential function for diatomic molecules. In terms of the energy spectrum expression of the deformed modified Rosen–Morse potential model, we obtain exact closed-form expressions for diatomic anharmonicity constants ωexe and ωeye . The anharmonicity constants for the X1Σ+g state of the N2 molecule have been computed and compared with the observed data.