Orthorhombic SrHfO3 (0 0 1) surfaces: Surface structure and electronic properties with first-principles calculations

Structural, electronic and surface properties of the (0 0 1) surface of orthorhombic SrHfO3 have been investigated with both SrO and HfO2 termination using the plane-wave ultrasoft pseudopotential technique based on the first-principles density-functional theory. The calculated results show the same changed trend of the interplanar distance of two slabs, the reduced band gaps of two slabs by comparison with those of bulk system, the weakened covalent surface in the HfO2-terminated slab and the weakened ionic surface in the SrO-terminated slab. The calculated surface energies indicate the cleavability of the orthorhombic (0 0 1) surface is harder than that of cubic (0 0 1) surface. The grand thermodynamic potential shows the SrO-terminated slab is more stable.