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Correlation effects in MgO and CaO: Cohesive energies and lattice constants

Klaus Doll·Michael Dolg·Hermann Stoll
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Abstract

A recently proposed computational scheme based on local increments has been applied to the calculation of correlation contributions to the cohesive energy of the CaO crystal. Using ab-initio quantum chemical methods for evaluating individual increments, we obtain 80% of the difference between the experimental and Hartree-Fock cohesive energies. Lattice constants corrected for correlation effects deviate by less than 1% from experimental values, in the case of MgO and CaO.

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Klaus Doll, Michael Dolg, Hermann Stoll. 1996-09-02. Correlation effects in MgO and CaO: Cohesive energies and lattice constants. https://doi.org/10.1103/physrevb.54.13529

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