An investigation was made of the effects of oxygen vacancies upon the adhesion behavior of incoherent Ni/MgO(001) interfaces with large misfit, based upon density functional theory. It was demonstrated that oxygen vacancies at any local atomic configuration of the incoherent geometry enhanced the image-chargelike interaction between the ions in MgO and the ion-induced images in Ni, and stabilize adhesion of the Ni/MgO(001) interface. The adhesion energy of the defective interface was markedly larger than that of the perfect interface. It was also shown that the force constants of the adhesive interactions near to the oxygen vacancies were comparable to the Ni–Mg bond at the perfect interface. The vacancy-induced enhancement of the image electron accumulation hardly contributed to the interfacial stiffness, while it was reduced by losing the covalent Ni–O interaction due to an on-top oxygen vacancy.

Effects of Oxygen Vacancy on Adhesion of Incoherent Metal/Oxide Interface by First-Principles Calculations. D.Matsunaka, Y.Shibutani: Surface Science, 2010, 604[2], 196-200