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Structures and Stabilities of Doubly-charged (MgO)nMg2+ (n=1-29) Cluster Ions

Andres Aguado·Francisco Lopez-Gejo·Jose M. Lopez
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Abstract

Ab initio perturbed ion plus polarization calculations are reported for doubly-charged nonstoichiometric (MgO)nMg2+ (n=1-29) cluster ions. We consider a large number of isomers with full relaxations of the geometries, and add the correlation correction to the Hartree-Fock energies for all cluster sizes. The polarization contribution is included at a semiempirical level also for all cluster sizes. Comparison is made with theoretical results for neutral (MgO)n clusters and singly-charged alkali-halide cluster ions. Our method is also compared to phenomenological pair potential models in order to asses their reliability for calculations on small ionic systems. The large coordination-dependent polarizabilities of oxide anions favor the formation of surface sites, and thus bulklike structures begin to dominate only after n=24. The relative stabilities of the cluster ions against evaporation of a MgO molecule show variations that are in excellent agreement with the experimental abundance spectra.

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Andres Aguado, Francisco Lopez-Gejo, Jose M. Lopez. 1998-12-10. Structures and Stabilities of Doubly-charged (MgO)nMg2+ (n=1-29) Cluster Ions. https://doi.org/10.1063/1.478366

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