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Ground-state properties of rutile: electron-correlation effects

Krzysztof Rosciszewski·Klaus Doll·Beate Paulus·Peter Fulde·Hermann Stoll
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Abstract

Electron-correlation effects on cohesive energy, lattice constant and bulk compressibility of rutile are calculated using an ab-initio scheme. A competition between the two groups of partially covalent Ti-O bonds is the reason that the correlation energy does not change linearly with deviations from the equilibrium geometry, but is dominated by quadratic terms instead. As a consequence, the Hartree-Fock lattice constants are close to the experimental ones, while the compressibility is strongly renormalized by electronic correlations.

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Krzysztof Rosciszewski, Klaus Doll, Beate Paulus, Peter Fulde, Hermann Stoll. 1998-04-14. Ground-state properties of rutile: electron-correlation effects. https://doi.org/10.1103/physrevb.57.14667

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