Neutron diffraction study of RPtGe2 (R = Dy, Ho) compounds

Magnetic structures of ternary RPtGe2 R = Dy,Ho compounds are determined by neutron diffraction on polycrystalline samples. The compounds crystallize in space group Immm. In DyPtGe2 the magnetic structure at 4 K is sine modulated and is characterized by the wave vector k(1) = [0.268, 0, 0]. It is transformed at 8 K into a structure also sine modulated with the wave vector k(2) = [0.495, 0, 0] and changes from a longitudinal to a nearly transverse type. The ordered Dy moments are 9.9 mu(B), and 8.5 mu(B) at 4 and 8 K, respectively. In HoPtGe2 the magnetic structure at 4.2 R is a canted antiferromagnetic. The ordered moments at Ho sites 4i and 4h are 8.1 mu(B) and 4.0 mu(B), at 4.2 K and are aligned within the ab- and bc- plane, respectively. (C) 2000 Elsevier Science B.V. AII rights reserved.