System for interpolating work function for a cold-field emitter

Simulating electron emission current density [Formula: see text] from a hemispherical cold-field emitter requires work function [Formula: see text] and field [Formula: see text] over the surface of the emitter. Typically, the surface is approximated by a polygonal tile model with polygons whose normals may point in a variety of directions, representing arbitrary facet planes. As [Formula: see text] has only been experimentally determined on a few planes of tungsten, the simulation must infer the work function for these nonstandard directions. This paper presents and demonstrates this interpolation system as tailored to crystals with three or more known crystallographic work functions.