Magnetic studies of intermetallic compounds Al3R (Al11R3) both in the solid and liquid states

The magnetic susceptibility of Al₃R and Al₁₁R₃ (R = Ce, Pr, Sm, Gd, Dy, Ho, Yb) compounds is investigated over wide temperature (300–1900 K) and field (0.2–1.2 T) ranges. It is found that microinclusions of Al₂R can exist in the samples. They are not detectable in ordinary X-ray diffraction but give a significant contribution to the magnetic properties. The average effective magnetic moment per rare-earth atom changes through the rare-earth metals line reaching its maximum for holmium but rather lower than for the pure rare-earth metals. It means that rare-earth elements form covalent bonds with aluminum. These bonds remain in the liquid phase and begin to break down after melting point of Al₂R only. The transition into a true solution state of the melt is somewhere above 1900 K.