Application of extended-Rydberg parameters in general Morse potential functions

The 3-parameter Rydberg and the 4-parameter general Morse functions have been adopted for describing bond-stretching in computation of molecular systems and many-body solid state systems. However the Extended-Rydberg function, such as the 5-parameter Murrell-Sorbie potential, has so far been confined to describing bond-stretching in very small molecules. Due to the superior functional flexibility of the Murrell-Sorbie potential, these parameters are converted into those of the general Morse potential due to the latter’s application in computational chemistry. Imposition of (a) equal minimum well-depth curvature, and (b) equal equilibrium-to-dissociation energy integral on both functions enable the repulsive and the attractive indices of the general Morse potential to be extracted. Comparison of the Murrell-Sorbie energy of CO, FSi, MgS and ClLi with the converted general Morse energy exhibits very good correlation.