UNIVERSAL DISSOCIATION-ENERGY RELATIONSHIPS FOR DIATOMIC-MOLECULES

If De and Re are the dissociation energy and internuclear distance of a diatomic molecule αβ, where α and β are elements from columns A and B of the periodic table, with atomic numbers Zα and Zβ, it is shown empirically that to fair accuracy De/R3eZαZβ = 4πC- exp(-ξRe) and D 1 3e(ZαZβ) η 3 = Hln(ZαZβ) + H′ as a ranges through A or β ranges through B. For the whole periodic table η ≈ 0.45. C′ ≈ 0.0024, ξ ≈ 2.00, H ≈ 0.16 and H′ ≈ 0.32. These relations are shown to follow from a physical model previously developed for harmonic force constants by Anderson and Parr, and from an argument based on the simple bond charge model of Politzer. © 1979.