TY - JOUR
T1 - First-principles study of defect energetics in titanium-doped alumina
AU - Matsunaga, Katsuyuki
AU - Nakamura, Atsutomo
AU - Yamamoto, Takahisa
AU - Ikuhara, Yuichi
PY - 2003/12/9
Y1 - 2003/12/9
N2 - First-principles plane-wave pseudopotential calculations were performed to study electronic structures, structural relaxation, and energetics of point defects in Ti-doped Al2O3. Substitutional and interstitial Ti ions with charge compensating intrinsic defects were considered, and their formation energies were evaluated under various atomic chemical potentials. It was found that substitutional Ti4+ ions with charge compensating Al vacancies were most stable in the oxidized condition. In contrast, as oxygen chemical potentials decreased, the formation energy of substitutional Ti3+ decreased to have the smallest value in the relatively reduced conditions. However, in the intermediate range of oxygen potentials, substitutional Ti3+ and Ti4+ exhibited similar formation energies, indicating that these Ti defects can coexist in a particular reduction environment.
AB - First-principles plane-wave pseudopotential calculations were performed to study electronic structures, structural relaxation, and energetics of point defects in Ti-doped Al2O3. Substitutional and interstitial Ti ions with charge compensating intrinsic defects were considered, and their formation energies were evaluated under various atomic chemical potentials. It was found that substitutional Ti4+ ions with charge compensating Al vacancies were most stable in the oxidized condition. In contrast, as oxygen chemical potentials decreased, the formation energy of substitutional Ti3+ decreased to have the smallest value in the relatively reduced conditions. However, in the intermediate range of oxygen potentials, substitutional Ti3+ and Ti4+ exhibited similar formation energies, indicating that these Ti defects can coexist in a particular reduction environment.
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U2 - 10.1103/PhysRevB.68.214102
DO - 10.1103/PhysRevB.68.214102
M3 - Article
AN - SCOPUS:1642452984
VL - 68
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 21
ER -