Beschreibung:
<jats:p>Neutron powder diffraction experiments were performed on the moderate Kondo systems Ce6Ni1.67Si3 and Ce5Ni1.85Si3. These measurements have shown that Ce6Ni1.67Si3 does not present a long range magnetic order down to 1.6 K, but only short range ferromagnetic correlations. Ce5Ni1.85Si3 undergoes an antiferromagnetic transition at TN ≈ 6 K. Its magnetic structure at 1.5 K and zero field is collinear with the magnetic moments along the hexagonal axis and can be described with the propagation vector k = (1/2 0 0). This antiferromagnetic order coexists with a short range ferromagnetic component.</jats:p>