Abstract
Flash sintering experiments of ceramics indicate the formation of a state far from equilibrium. It is hypothesized that this state is enriched by Frenkel defects. The possibility is investigated that such lattice defects are being generated by a proliferation of lattice vibrations that lie close to the Brillouin zone edge. We show by means of Molecular Dynamics simulations of rutile TiO2 that this mechanism generates Frenkel defects in concentrations far beyond equilibrium. These defects deform the whole lattice in a way that the mean鈥恠quare displacements of the vibration amplitudes of the Ti and O atoms are specifically enhanced. This finding compares well to atomic displacement data of ash sintered rutile TiO2 reported recently.