Polarized neutron study of the RA12 compound: I. Magnetization density in NdA12

The magnetization density of the ferromagnet NdA1₂ has been studied by diffraction of polarized neutrons on single crystals. The data have been treated as well in direct space using Fourier transformation techniques as in reciprocal space with the tensor operator method. The two treatments give the same result: besides the localized magnetization due to the 4f electrons of Nd, and corresponding to 2.61 μ_B, there exist another magnetization, opposite to the first one, which fluctuates throughout the cell with a pronounced extremum around the Nd atoms. Its integrated value is -0.14 μ_B/ND. The 4f electron wave function corresponding to the localized magnetization has been determined.