6533b855fe1ef96bd12b110c

RESEARCH PRODUCT

Semi-empirical simulations of surface relaxation for perovskite titanates

Joachim MaierEugene A. KotominEugene A. KotominEugene Heifets

subject

ChemistryRelaxation (NMR)MineralogySurfaces and InterfacesCondensed Matter PhysicsMolecular physicsSurface energySurfaces Coatings and FilmsIonPseudopotentialDipolechemistry.chemical_compoundMaterials ChemistryStrontium titanateThin filmPerovskite (structure)

description

The (100) and (110) surface relaxations are calculated for SrTiO 3 and BaTiO 3 perovskite thin films. By means of a semi-empirical shell model, the positions of atoms in 16 near-surface layers placed atop a slab of rigid ions are calculated. Surface rumpling and surface-induced dipole moments are calculated for all possible surface terminations. Our results for the (100) surface structure are in good agreement with ab-initio plane-wave pseudopotential calculations and LEED experiments. The surface energy for the Ba-, Sr-, TiO-terminated (110) surfaces is found to be much larger than that for the (100) surface. In contrast, the surface energy for the asymmetric O termination, where outermost O atoms are strongly on-plane-displaced, is the lowest for all (110) terminations and thus the most stable. © 2000 Elsevier Science B.V. All rights reserved.

https://doi.org/10.1016/s0039-6028(00)00603-8