First-principles study of a tilt grain boundary in rutile

The atomic and electronic structure of a tilt grain boundary in rutile ${\mathrm{TiO}}_2$ has been calculated in an ab initio manner. The method employs a plane-wave basis set and optimized pseudopotentials and is carried out within the local-density approximation of density-functional theory. The study focuses on the structure and energy of the ∑=15 36.9° (210)[001] tilt boundary, which is relaxed to equilibrium using a conjugate gradients iterative minimization technique. The calculations confirm the stability of a proposed atomic model for the boundary and provide some insight into its electronic structure. © 1996 The American Physical Society.