ATOMIC-STRUCTURE OF A 36.8(210) TILT GRAIN-BOUNDARY IN TIO2

An understanding of the atomic structure at internal interfaces is of crucial importance for the electronic and structural properties of mos t advanced materials. Here, me present a detailed study of the atomic structure at a [001] tilt grain boundary of Sigma 5(210) in TiO2 (ruti le). Z-contrast imaging is used to obtain a 2-D atomic map of the cati on positions at the interface. Details of the charge state of cations and atomic structure around anion sites are then provided using electr on energy loss spectroscopy, In particular, the spectroscopic data for oxygen is interpreted using multiple scattering theory to give 3-D st ructural information. These combined techniques allow a unique grain b oundary structure to be defined.