Antiferromagnetic ordering of TbH2+x

Abstract
Tb dihydride TbH2+x has been investigated for −0.05N depend strongly on x. For x≊−0.05, a commensurate antiferromagnetic structure appears below 15.8 K. For higher concentrations different incommensurate structures are obtained which are stable from TN down to 4 K. The transition from the commensurate into an incommensurate magnetic structure is ascribed to the random occupation of some octahedral sites in the fcc Tb lattice for x≳−0.05.