Neutron diffraction determination of magnetic ordering in the U 1− xTh xAs system: Evidence for modulated magnetic phases

Abstract

Magnetic structures and ordered magnetic moments of U 1− x Th x As ( x ≤ 0.30) with NaCl structure were determined by means of neutron diffraction on single crystal samples. In addition to configurations I(+-), IA(++--) with magnetic moments oriented along the 〈100〉 directions and ferromagnetic planes perpendicular to these axes, further antiferromagnetic phases corresponding to longitudinal 〈100〉 modulations exist. Their periods depend on composition and vary for x ≤ 0.20 continuously with temperature.