Surface energy and excess charge in (1x2)-reconstructed rutile TiO2(110) from DFT plus U calculations

Physically reasonable electronic structures of reconstructed rutile TiO2(110)-(1x2) surfaces were studied using density functional theory (DFT) supplemented with Hubbard U on-site Coulomb repulsion acting on the d electrons, the so called DFT + U approach. Two leading reconstruction models proposed by Onishi and Iwasawa [Surf. Sci. Lett. 313, 783 (1994)] and Park and coworkers [Phys. Rev. B 75, 245415 (2007)] were compared in terms of their thermodynamic stabilities.