Ion-rare gas interactions on the repulsive part of the potential curves

Abstract

Interaction potentials for alkali ion-rare gas and halogen ion-rare gas systems J. Chem. Phys. 88, 6290 (1988); 10.1063/1.454467 Comment on ''Recent determinations of potassium ion-rare gas potentials'' Potential energy curves from the electron gas model. II. The ion-rare gas interactionsInteractions of the rare gas atoms with some alkali and halide ions are treated using the model presented in our previous paper [J. Chern. Phys. 56, 3122 (1972)]. In the calculation of the interactions of an atom and an ion. the electron density of the combined system is assumed to be equal to the sum of the two separate electron densities. The Coulombic energy contribution to the interaction energy is calculated directly from the charge distribution of the nuclei and the assumed electron density. The non-Coulombic part of the interaction energy is calculated from the electron density by integrating the uniform electron gas energy expression over the local electron density. The calculated potential curves agree very well with available experimental results over the entire repulsive wall. At larger distances, the model fails. because in its present form it does not include induction forces.The total interaction energy between these two systems is then separated into two parts, the Coulombic and the non-Coulombic parts. The non-Coulombic part of the interaction energy is evaluated using the electron gas energy expression in terms of the local denSity:

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