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First-principles and semi-empirical calculations for bound hole polarons in KNbO3

E. A. Kotomin·R. I. Eglitis·A. V. Postnikov·G. Borstel·N. E. Christensen
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Abstract

The ab initio linear muffin-tin-orbital (LMTO) formalism and the semi-empirical method of the Intermediate Neglect of the Differential Overlap (INDO) based on the Hartree-Fock formalism are combined for the study of the hole polarons (a hole trapped nearby the cation vacancy) in a cubic phase of KNbO3 perovskite crystals. The 40-atom and 320-atom supercells were used, respectively. We predict existence of both, one-site and two-site (molecular) polarons with close optical absorption energies (0.9 eV and 0.95 eV). The relevant experimental data are discussed.

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E. A. Kotomin, R. I. Eglitis, A. V. Postnikov, G. Borstel, N. E. Christensen. 1999-03-24. First-principles and semi-empirical calculations for bound hole polarons in KNbO3. https://doi.org/10.1103/physrevb.60.1

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