Small ordered magnetic moment in a weak itinerant electron ferromagnet Sc3In

CaMn2Al10: Itinerant Mn magnetism on the verge of magnetic order

“…With T C constrained to ≤ 1.8 K, the RW curve predicts µ CW /µ S ≥ 8 for CaMn 2 Al 10 . If it does indeed order, this ratio, combined with the small fluctuating moment we calculate from χ(T ), yields a spontaneous moment µ S ≤ 0.1 µ B , some two orders of magnitude smaller than the high spin Hund's rule value and consistent with the value of M (H) at 7 T. Perhaps CaMn 2 Al 10 is most comparable to Sc 3 In, which has an ordered moment of only 0.04-0.05 µ B [60]. Considering that Mn-based compounds are generally strongly magnetic, while those based on Sc are nearly always nonmagnetic, both Sc 3 In and CaMn 2 Al 10 appear as remarkable and extreme members even among weak itinerant FM.…”