A Simple Three-Parameter Model Potential For Diatomic Systems: From Weakly and Strongly Bound Molecules to Metastable Molecular Ions

Abstract

Based on a simplest molecular orbital theory of H${}_2^{+}$, a three-parameter model potential function is proposed to describe ground-state diatomic systems with closed-shell and/or S-type valence-shell constituents over a significantly wide range of internuclear distances. More than 200 weakly and strongly bound diatomics have been studied, including neutral and singly-charged diatomics (e.g., H${}_2$, Li${}_2$, LiH, Cd${}_2$, Na${}_2^{+}$, and RbH${}^{-}$), long-range bound diatomics (e.g., NaAr, CdNe, He${}_2$, CaHe, SrHe, and BaHe), metastable molecular dications (e.g., BeH${}^{++}$, AlH${}^{++}$, Mg${}_2^{++}$, and LiBa${}^{++}$), and molecular trications (e.g., YHe${}^{+++}$ and ScHe${}^{+++}$).

5 pages, 4 figures, accepted by Physical Review Letters