A Note on the Thermionic Work Function of Tungsten

Correction for the Schottky Effect has been applied to our measurements upon the thermionic work function of tungsten. For zero field at the filament we obtain the value 4.82 volts for φ₂ in the equation i=AT1/2 exp. (-φ₂ekT) and, as before, the value 4.91 volts as the equivalent voltage of the work function measured calorimetrically at 2270^∘{}K. Careful consideration shows that the difference of 0.09 volt between these quantities must be interpreted as evidence that conduction electrons within the filament do not possess normal thermal energies, and that no evidence is offered by this experiment regarding the surface heat of charging.