Molecular energies of the improved Rosen-Morse potential energy model

We solve the Schrodinger equation with the improved Rosen-Morse empirical potential energy model. The rotation-vibrational energy spectra and the unnormalized radial wave functions have been obtained. The interaction potential energy curves for the 3(3)Sigma(+)(g) state of the Cs-2 molecule and the 5(1)Delta(g) state of the Na-2 molecule are modeled by employing the improved Rosen-Morse potential and the Morse potential. Favourable agreement for the improved Rosen-Morse potential is found in comparing with the Rydberg-Klein-Rees potential. The vibrational energy levels predicted by using the improved Rosen-Morse potential for the 3(3)Sigma(+)(g) state of Cs-2 and the 5(1)Delta(g) state of Na-2 are in better agreement with the Rydberg-Klein-Rees data than the predictions of the Morse potential.