Rigid-body displacement perpendicular to a symmetrical {112} grain boundary
in a Sigma = 3 Mo bicrystal was measured using the x-fringe method. The gr
ain boundary contained a set of parallel intrinsic dislocations accommodati
ng the deviation from the exact coincidence. The observed images were compa
red with theoretical image simulations. This procedure enabled us to elimin
ate the influence of dislocations on the measurement of the displacement. T
he result was compared with the expansion previously determined by high-res
olution electron microscopy and by theoretical atomic simulations.