B. Kirchner et al., A CALCULATION OF THE TEMPERATURE-DEPENDENT SUSCEPTIBILITY OF PD AND DILUTE PD1-XAGX AND PDHX ALLOYS, Journal of physics. Condensed matter, 6(13), 1994, pp. 2603-2618
The temperature dependence of the magnetic properties of itinerant ele
ctron systems is mainly due to the excitation of spin fluctuations. We
calculate the susceptibilities of Pd, Pd1-xAgx, and PdH(x) (0 less-th
an-or-equal-to x less-than-or-equal-to 0.03) with an extension of the
classical Murata-Doniach model for spin fluctuations, which treats the
energy functional without a Landau expansion of the magnetization-dep
endent ground state energy. To obtain this energy ASW (augmented spher
ical wave) and KKR-CPA bandstructure calculations are performed. In ag
reement with experiment the KKR-CPA method yields a maximum of chi(T)
for Pd, which disappears with increasing Ag concentration. In the Asw
calculations, low Ag and H concentrations are simulated by the superce
lls Pd31Ag and Pd32H. In addition the alloy PdH(x) is simulated by cal
culations for pure Pd, with the valence electron concentration increas
ed suitably. Calculations of the susceptibility of Pd within the frame
work of the Stoner theory and the spin fluctuation theory based upon t
he rigid-band model are presented. The role of the electron interactio
n in both theories is examined and the reason for the maximum of chi(T
) for Pd is investigated. We find the different scaling of the tempera
ture axis in the Stoner and spin fluctuation theories to have its orig
in in a different treatment of the electron interaction.