Theoretical evidence for unexpected O-rich phases at corners of MgO surfaces

Abstract

Realistic oxide materials are often semiconductors, in particular at elevated temperatures, and their surfaces contain undercoordiated atoms at structural defects such as steps and corners. Using hybrid density-functional theory and ab initio atomistic thermodynamics, we investigate the interplay of bond-making, bond-breaking, and charge-carrier trapping at the corner defects at the (100) surface of a p-doped MgO in thermodynamic equilibrium with an O2 atmosphere. We show that by manipulating the coordination of surface atoms one can drastically change and even reverse the order of stability of reduced versus oxidized surface sites.

5 papges, 4 figures

References in corpus (2)

• Embedded-Cluster Calculations in a Numeric Atomic Orbital Density-Functional Theory Framework
• Efficient ab initio schemes for finding thermodynamically stable and metastable atomic structures: Benchmark of cascade genetic algorithms

Cited by in corpus (1)

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