The Relation Between the Electron Field Emission and the Work Function of Liquid Mercury

Abstract

The variation in the field necessary to initiate a vacuum discharge between a mercury cathode and a molybdenum anode and the accompanying variation in the work function of the cathode have been measured. The work function variations were obtained from measurements of the contact potential between the mercury and a platinum filament. The fields were applied by an impulse circuit, the time constant of the voltage wave being very short in order to prevent distortion of the mercury. The final results show a variation of the field with work function which, while in the same direction, is more pronounced than that forecast by the Fowler-Nordheim theory. For a change of work function of one volt the field required to initiate the discharge varied from 375 kv/cm to 575 kv/cm.