Universal nature of diatomic potentials

A simple mathematical technique is introduced to establish the connection between the universality of diatomic potentials and correlation property of the Graves-Parr parameters ${\mathrm{\beta }}_1^2$ (=${\mathit{a}}_1^2$/Δ) and ${\mathrm{\beta }}_2$ (=${\mathit{a}}_2$/Δ) [Phys. Rev. A 31, 1 (1985)]. On the basis of this universal feature of diatomic potentials, an accurate expression of the ground-state reduced potential valid for all diatomic molecules has been obtained.