“…Here, as the facet around the (0 0 2) pole gets flatter, one could assume that this results in a relative decrease of the electric field at the apex, thus in an increase of k f with the radius, conversely to what is effectively observed. The experimental trend was, however, expected from the work of Gipson et al [45,46], where a finite-element method and was used to estimate the electric field in the vicinity of a field-ion microscopy specimen in a realistic microscope geometry. They proposed an advanced description of the field factor that accounts not only for the divergence from sphericity, but also for the far-field geometry and parameters specific to the specimen, such as its length, size, radius of curvature or shank angle.…”