Abstract
We examine the relative stability of both stoichiometric and nonstoichiometric interfaces and surfaces. Results of first-principles computations of surface and interfacial atomic relaxations, electron-density distributions, and total energies are presented. We found that while the Al-terminated surface is stable relative to the O-terminated surface, interface formation with Nb can reverse the stability, depending on the oxygen partial pressure. This interfacial structure is consistent with recent experimental results. Finally, we computed some of the energetics associated with the diffusion of Al into Nb across the interface. Our results are consistent with Al migration into the Nb at temperatures of the order of as reported experimentally.
- Received 14 February 2000
DOI:https://doi.org/10.1103/PhysRevB.61.16883
©2000 American Physical Society