Magnetic Structure versus Electron Number for Some Rare-Earth Intermetallic Compounds

Abstract

Neutron diffraction measurements were made on a series of rare‐earth compounds in the Tb(Pd, Ag) and Tb(Ag, In) systems. Most of these compounds exhibit the CsCl type of crystal structure and, for these, magnetic structure determinations were made in order to relate the type of magnetic structure to the number of valence electrons. Two types of antiferromagnetic structures were observed; the (ππ0) type consisting of an antiparallel array of ferromagnetic (110) planes of moments, and the (00π) type with ferromagnetic (001) planes of moments alternating in direction. On the basis of 0, 1, 3, and 3 valence electrons for Pd, Ag, In, and Tb, respectively, the (ππ0) structure is found in the region of 3.5 to 4 valence electrons per unit cell and the (00π) structure in the region of 5 valence electrons per unit cell.