(ABSTRACT) We analyze the lattice walk performed by a tagged member of an infinite 'sea' of particles filling a d-dimensional lattice, in the presence of a single vacancy. The vacancy is allowed to be occupied with probability 1/2d by any of its 2d nearest neighbors, so that it executs a Brownian walk. Particle-particle exchange is forbidden; the only interaction between them being hard core ex...

In materials science the phase-field crystal approach has become popular to model crystallization processes. Phase-field crystal models are in essence Landau-Ginzburg-type models, which should be derivable from the underlying microscopic description of the system in question. We present a study on classical density functional theory in three stages of approximation leading to a specific phase-f...

The energetics of Ni vacancy jumps in the intermetallic compound NiAl are studied by combining embedded-atom and first-principles calculations. The embedded-atom potential used in this work is fit to both experimental and first-principles data and provides an accurate description of point defect energies and vacancy jump barriers in NiAl. Some of the embedded-atom results reported here, are ind...

In this paper a Frenkel–Kontorova model with a nonlinear interaction potential is used to describe a vacancy defect in a crystal. According to recent numerical results [Cuevas et al. Phys. Lett. A 315, 364 (2003)] the vacancy can migrate when it interacts with a moving breather. We study more thoroughly the phenomenology caused by the interaction of moving breathers with a single vacancy and al...

While it is being debated whether Cd vacancy is an effective p-dopant in CdTe, and whether CdTe thin film in solar energy application should be Cd-deficient or Cd-rich, in the theory of CdTe physical vapor deposition (PVD) it has been assumed that both the source material and the thin film product is stoichiometric. To remediate the lack of effective theory, a new PVD model for CdTe photovoltai...

First principles calculations using density functional theory with corrections for on-site Coulomb interactions (DFT + U) are presented in which we compute the energy for the conversion of CO to CO(2), NO(2) to NO and NO to N(2) over ceria surfaces. The surface sensitivity is discussed on the basis of the vacancy formation energies.