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arXiv · 1405.3732

Exceptionally Long-ranged Lattice Relaxation in Oxygen-deficient Ta2O5

Yong Yang·Osamu Sugino·Yoshiyuki Kawazoe
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Abstract

The lattice relaxation in oxygen-deficient Ta2O5 is investigated using first-principles calculations. The presence of a charge-neutral oxygen vacancy can result in a long-ranged lattice relaxation which extends beyond 18 Å from the vacancy site. The lattice relaxation has significant effects on the vacancy formation energy as well as the electronic structures. The long-ranged behavior of the lattice relaxation is explained in terms of the Hellmann-Feynman forces and the potential energy surface related to the variation of Ta-O bond lengths.

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Yong Yang, Osamu Sugino, Yoshiyuki Kawazoe. 2014-05-15. Exceptionally Long-ranged Lattice Relaxation in Oxygen-deficient Ta2O5. https://doi.org/10.1016/j.ssc.2014.06.021

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