Magnetic susceptibility of chromium-ruthenium alloys between 300 and 600 K

Magnetic susceptibility $\chi$ of chromium-ruthenium alloys containing 0.9-, 2.1-, 3.0-, 4.8-, 6.6-, 8.3-, and 10.1- at.% ruthenium has been measured as a function of temperature $T$ between 300 and 600 K. Each of the $\chi$ vs $T$ curves exhibits a well-defined knee at the Néel temperature $T_N$. Experimental results indicate that there is no localized magnetic moment on ruthenium atoms above $T_N$. The temperature dependence in the antiferromagnetic region between 350 K and $T_N$ is described by extending the Fedders-Martin theory for itinerant-electron antiferromagnets.