Determination of the orientation in small areas of the exit wave.

Local differences in thickness and misorientation in a through-focus reconstructed exit wave hamper direct interpretation. These local thicknesses and misorientations can be refined on an atomic scale using the intensities of the Fourier components with the refinement procedure in which a least-squares refinement is combined with a multi-slice calculation. The method was applied to the superconductor La3Ni2B2N3. The crystal tilt and specimen thickness can be determined with an R-value of 8-25%, with a better R-value for thinner areas. Significant differences in the refined tilts, thicknesses and R-values are observed when reconstructed exit waves that are corrected for mechanical vibration are compared with reconstructed exit waves, which are uncorrected.