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First-principles study of structural, vibrational and lattice dielectric properties of hafnium oxide

Xinyuan Zhao·David Vanderbilt
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Abstract

Crystalline structures, zone-center phonon modes, and the related dielectric response of the three low-pressure phases of HfO2 have been investigated in density-functional theory using ultrasoft pseudopotentials and a plane-wave basis. The structures of low-pressure HfO2 polymorphs are carefully studied with both the local-density approximation (LDA) and the generalized gradient approximation (GGA). The fully relaxed structures obtained with either exchange-correlation scheme agree reasonably well with experiment, although LDA yields better overall agreement. After calculating the Born effective charge tensors and the force-constant matrices by finite-difference methods, the lattice dielectric susceptibility tensors for the three HfO2 phases are computed by decomposing the tensors into the contributions from individual infrared-active phonon modes.

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Xinyuan Zhao, David Vanderbilt. 2002-02-25. First-principles study of structural, vibrational and lattice dielectric properties of hafnium oxide. https://doi.org/10.1103/physrevb.65.233106

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