Determining the three-dimensional atomic structure of
grain boundaries is a crucial first step toward understanding how these
defects control the overall bulk properties of materials. In this
report we discuss the correlation of experimental atomic resolution
Z-contrast images and electron energy loss spectrometry (EELS) to
achieve this goal. Initial structural analysis is afforded through
empirical bond-valence potentials. This structure is then refined using
multiple scattering analysis of the energy loss spectra. These
techniques are demonstrated in the analysis of a 27° MgO [001]
tilt grain boundary. Through this analysis, we were able to determine
specific atomic locations of Ca dopants found present at this grain
boundary.