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RESEARCH PRODUCT

Atomic and electronic structure of perfect and defective PbZrO3 perovskite: Hybrid DFT calculations of cubic and orthorhombic phases

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Abstract The structural and electronic properties of pure cubic and low-temperature orthorhombic PbZrO3 (antiferroelectric phase), as well as cubic PbZrO3 containing single F-centers (neutral oxygen vacancies) have been simulated by means of ab initio hybrid density functional calculations. We observed a substantial increase of the Pb–O bond covalency in ideal orthorhombic PbZrO3 with respect to its cubic phase. Relatively large displacement of four Pb atoms nearest to the F-center (0.25 A towards the defect) could affect the PbZrO3 ferroelectric properties. An O vacancy in the bulk PbZrO3 attracts ≈0.7 e, and the remaining electron density from the missing O2− is localized mostly on four nearest Pb atoms. This leads to appearance of an energy level in the middle of the band gap of cubic PbZrO3, unlike the shallow F-level found in SrTiO3.