Magnetic properties of cerium hydrides at low temperatures

Abstract The magnetic properties of CeH x were investigated in the concentration range 1.8 x ⩾ 3.0. Susceptibility measurements from 300 K down to 1.3 K show different effective magneton numbers per cerium ion for different hydrogen concentrations. Deviations from Curie-Weiss behaviour due to crystal field effects are observed. The a.c. susceptibility data reveal distinct maxima at 4.2 K and 2.4 K for CeH 2.43 and CeH 3.00 respectively. We determined the type and structure of the magnetic order by means of high field magnetization measurements and neutron diffraction experiments. CeH 2.43 orders ferromagnetically, whereas CeD 3.0 shows an antiferromagnetic alignment of moments of 0.64 (7) μ B along the [111] direction.