Ab initio calculations of the SrTiO 3 „ 110 ... polar surface
نویسندگان
چکیده
Results of ab initio Hartree-Fock calculations for the SrTiO3 ~110! polar surface are discussed. We have calculated the surface energies, near-surface atomic displacements for four possible terminations ~TiO, Sr, and two kinds of O terminations! as well as Mulliken atomic charges and dipole moments of atoms characterizing their polarization, and the atomic bond populations. We predict a considerable increase of the TiuO chemical bond covalency near the ~110! surface, as compared to both the bulk and the ~100! surface. The O-terminated ~110! surface has surface energy close to that for ~100!, which indicates that both ~110! and ~100! SrTiO3 surfaces can coexist in polycrystals and perovskite ceramics.
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