In order to compare Cu adhesion upon two kinds of perfect cubic (001) oxide surfaces: (i) TiO2- and BaO-terminated substrates of partly covalent BaTiO3 and (ii) highly ionic MgO substrate, we have performed DFT-LCAO calculations using a hybrid B3PW Hamiltonian. 2D symmetrical slabs used here contain seven BaTiO3 and five MgO substrate layers covered on both sides by submonolayers of ordered Cu atoms. The Cu periodic coverage density atop the surface oxygen anions was varied from 1/8 to 1/2 monolayer. Copper bonding on the BaTiO3(001) surface has been found to be noticeably stronger than that on ionic MgO(001). Cu adatoms attract the electron density from BaO-terminated and donate it towards TiO2-terminated BaTiO3(001) substrates, respectively, by an amount that is about threefold larger than for a Cu/MgO(001) interface.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics