NEUTRON-DIFFRACTION STUDIES OF PR2C3, ND2C3, AND DY2C3 AT 300 TO 1.6-DEGREES-K

Neutron diffraction measurements have shown that the body-centered cubic Pr2C3, Nd2C3, and Dy2C3 become antiferromagnetic below 8, 24, and 22°K, respectively, all exhibiting the Tb2C3-type magnetic structure. In the uniaxial moment model having two antiferromagnetic and two paramagnetic body diagonals, the saturation order moments per metal atom are 1.3, 3.0, and 9.5 Bohr magnetons, respectively, being 41, 92, and 95% of the respective free ion values. Pr2C3 shows an exceptionally large crystal field effect. The antiferromagnetic alignment is uninfluenced by the applied field of up to 21 kOe. The crystal structure data at 300 to 1.6°K are also given. A brief review is presented on the physical properties of the rare earth sesquicarbides. © 1978.