| Popis: |
Electronic band and structural properties of the cubic, tetragonal, and monoclinic phases of HfO2 are calculated. The all electron ab initio self-consistent linear augmented plane-wave method within the framework of the local-density approximation was used, and full-relativistic contributions were taken into account. For the cubic phase, the lattice constant was obtained through a total energy minimization. For the tetragonal phase, the lattice parameters were calculated from the equilibrium volume obtained by variation of the ratio c/a, besides the relaxation of internal parameters (atomic positions). The monoclinic phase was studied using parameters as extracted from previous theoretical calculations. The electronic band structures for the three different structural phases present the same chemical trends relative to energy band gaps and valence-band states. The relativistic and spin–orbit effects are more pronounced for deep valence states. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) |
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