The temperature dependence of magnetization of Gd-Tb alloys

It is shown that a mean field theory can describe very closely the variation of magnetization with temperature found in a series of Gd-Tb alloys. The proportionality of the exchange constants to the density of the states at the Fermi energy has been confirmed. The values for the densities of states for Gd and Tb required for satisfactory fitting of the experimental results are in agreement with values calculated from electronic specific heat measurements.