The probability of ejection of an electron in the surface photo-effect is expressed in terms of a function of the potential barrier, the energy of the electron after ejection, and the frequency. This function is dominated, for low energies of ejection, by the transmission coefficient of the surface. It is then assumed that the function can be expanded in a power series in terms of the energy of the electron after ejection. In calculating the total emitted current it is shown that the power series development leads to a series of distinctive functions expressing the current in terms of the frequency and the stopping potential. Each of these functions has its own temperature dependence, so that from a complete knowledge of the energy distribution and the temperature dependence of the emitted current it would be possible to draw conclusions as to the nature of the potential barriers. By comparing the theoretical expressions with the observed curves of Overhage, and of Mann and DuBridge, it is possible to conclude that the transmission coefficient of Overhage's anode and of the sodium cathode used by Mann and DuBridge vanished linearly with the diminishing energy of the ejected electrons.

• Received 30 August 1937

DOI:https://doi.org/10.1103/PhysRev.52.1047