Application of the Platt Electrostatic Model to Diatomic Hydride Ions

Abstract

The Platt electrostatic model for calculating equilibrium internuclear distances and force constants of diatomic hydride molecules has been used to calculate properties of diatomic hydride ions. An empirical approach to the scaling technique proposed by Hall and Rees was employed in order to render the model consistent with the quantum mechanical virial theorem. This has the additional advantage of improving the calculated equilibrium properties. For twelve known hydride ions there is satisfactory agreement between calculated and experimentally measured force constants and equilibrium internuclear distances. The applicability of the relation Kre/D0=const. to a sequence of similar diatomic ions was briefly examined. Calculated values of K and re were used in the above relation to estimate dissociation energies of the rare-gas hydride ions. Results are compared with experimental limits determined from mass spectrographic investigations. Equilibrium properties of the corresponding neutral species calculated by the Platt electrostatic model are consistent with the generally assumed instability of the rare gas hydride molecules.