Element-specific displacements in defect-enriched TiO2: Indication of a flash sintering mechanism

M Jongmanns and DE Wolf, JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 103, 589-596 (2020).

DOI: 10.1111/jace.16696

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-square displacements of the vibration amplitudes of the Ti and O atoms are specifically enhanced. This finding compares well to atomic displacement data of flash sintered rutile TiO2 reported recently.

Return to Publications page