The Magnetic Structures of CeBi

Abstract
Neutron diffraction measurements were made on CeBi to determine the type of magnetic order which develops in this metamagnetic compound. In contrast to results obtained for polycrystalline samples, these single crystal measurements show two antiferromagnetic structures for this f.c.c. ( NaCl type) compound. The high temperature structure develops below 25.2°K and consists of ferromagnetic (00ℓ) layers of moments in a +−+− stacking sequence. At 12.5°K there is a first order transition to the low temperature structure which also has ferromagnetic (00ℓ) layers but in the sequence ++−−. For both structures, the moments are about 2.1 μB per Ce and are parallel to the c‐axes of the tetragonal magnetic unit cells.