Knight shifts and magnetic susceptibilities of the intermetallic compounds CeCu4 and CeCu5

The magnetic susceptibility and Knight shift of the compounds CeCu4 and CeCu5 have been measured over the temperature ranges 80 to 800 and 140 to 400 K, respectively. The most important contributions to the magnetic susceptibility are the Curie-Weiss term, expressing the paramagnetism of the localized f-electrons, and a temperature independent term, which have both been determined. The phenomenological exchange integral Fsub(sf) between the 4f-electron spins and conduction electron spins was found to be -10.43 x 10-3 eV for CeCu4 and 3.9 x 10-3 eV for CeCu5. A reversal in the sign of the s-f coupling for CeCu5 is noted. (author)