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arXiv · 1301.2842

The interactions of same-row oxygen vacancies on rutile TiO$_2$(110)

B. B. Kappes·W. B. Maddox·D. P. Acharya·P. Sutter·C. V. Ciobanu
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Abstract

Based on a dipolar-elastic model for oxygen vacancies on rutile (110), we evaluated analytically the overall energy of a periodic array of two vacancies and extracted the interaction parameters from total-energy density functional theory (DFT) calculations. Our calculations show that the dipole model holds for next-nearest neighbor vacancies and beyond. The elastic-dipolar interaction vanishes for adjacent vacancies, but they still experience an electrostatic repulsion. The proposed interaction model predicts a vacancy separation distribution that agrees well with that determined in our ultra-high vacuum scanning tunneling microscopy experiments, and provides a perspective for understanding earlier DFT reports.

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B. B. Kappes, W. B. Maddox, D. P. Acharya, P. Sutter, C. V. Ciobanu. 2013-01-14. The interactions of same-row oxygen vacancies on rutile TiO$_2$(110). https://doi.org/10.1103/physrevb.84.161402

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