Photoelectric Work Function from Analysis of Emission in an Accelerating Field

The photoelectric work function can be determined by analysis of monochromatic photoelectric emission in an accelerating field. A plot of $I$ vs $E^{\frac{1}{2}}$ gives a straight line for incident light a few tenths of an ev from the threshold. The ratio of the zero-field intercept to the slope of this line is directly proportional to $h(\nu -{\nu }_0)$ and is independent of the intensity of the incident light. The work function can be determined from this ratio for both metallic and semiconducting emitters. A graphical method is developed for eliminating the dependence of the determination on the field factor and the parameter, $m$, and the dielectric constant, $k_e$, in the emission equation for semiconductors. The work function of Te is determined by the present method from data of Apker, Taft, and Dickey. The value obtained, 4.78 ev, is in good agreement with their determination.