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arXiv · 1609.04760

Structures and finite-temperature abundances of defects in In$_2$O$_3$-II from first-principles calculations

Jamie M. Wynn·Richard J. Needs·Andrew J. Morris
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Abstract

We have studied intrinsic defect complexes in In$_2$O$_3$ using ab initio random structure searching (AIRSS). Our first-principles density-functional-theory calculations predict the thermodynamic stability of several novel defect structures. We combine the static lattice energy and harmonic vibrational energy with the often-neglected configurational entropy to construct the free energy, which is minimised to predict defect abundances at finite temperatures. We predict that some of our new defect structures - in particular our {In,2V$_\mathrm{O}$} and {2In,3V$_\mathrm{O}$} defects - can exist in significant abundances at finite temperatures, and their densities of electronic states indicate that they could play an important role in the unexpectedly high density of n-type charge carriers observed in In$_2$O$_3$.

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Jamie M. Wynn, Richard J. Needs, Andrew J. Morris. 2016-09-15. Structures and finite-temperature abundances of defects in In$_2$O$_3$-II from first-principles calculations. https://arxiv.org/abs/1609.04760

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