Crystals and magnetic structures of CeC2, PrC2 and NdC2

Neutron diffraction study has revealed that CeC2, PrC2 and NdC2 become a body-centered first-kind anti-ferromagnet below 33°, 15° and 29°K with the ordered moments having 81, 44 and 90% of the free-ion values, respectively. The moment direction is parallel to the tetragonal c-axis.