Alkali molecular ion energies and expectation values in a model-potential treatment

Publisher Website
Google Scholar
Abstract
By using Hellman‐type model potentials for alkali atoms, the many‐electron problem of the alkali molecular ions is reduced to a three‐body problem, and the ground state energy of the these ions calculated in the familiar Rayleigh‐Ritz variational treatment. All the ions result as being stable. Other physical quantities (equilibrium and mean distances, etc.) are also calculated. The reported data may be useful in a variety of scattering problems, such as, for instance, alkali atom‐ion collisions. They support the James' suggestion that the dissociation energies of the alkali molecular ions must be greater than those of the corresponding molecules, due to the greater diffuseness of the bonding wavefunctions. Application of the present approach to alkali hydride ions seems to indicate that these ions are not stable. The limitations of the pseudopotential approach for molecular calculations are discussed, and it is concluded that the approach is of simpler use for alkali molecular ions than for the corresponding molecules.