Thermal work function shifts for polycrystalline metal surfaces

摘要

A new approach is presented fnr the calculation of the thermal shifts of the work functions of polycrystalline metal surfaces by including the thermal expansion of the metal into the election density parameter as il ell as Fermi energy. Calculations of d phi /dT as a function of temperature are performed for 74 elements, encompassing a total of 103 cases of various temperature ranges, phases and (in a few cases) orientations. II is shown that for a majority of metals d phi /dT is not a constant over a broad temperature range. Comparison of theoretical and experimental values indicates that the thermal lattice vibrations do not influence d phi :dT significantly. Our results would suggest that the use of a Kelvin probe to measure the thermal variation of phi may be problematic. (C) 2001 Elsevier Science B.V. All rights reserved. References: 32