Hydrogenation of HoCu: Hydride formation and magnetic properties

The intermetallic compound HoCu is hydrogenated to form a composition HoCuH3. Magnetic properties of the hydride have been studied by magnetization, low temperature heat capacity and electrical resistivity measurements. While HoCu is antiferromagnetic with a Néel temperature of ∼27 K, the hydride does not show any indication of homogeneous long range magnetic ordering down to 1.6 K. The magnetization and the heat capacity measurements can be reconciled to a spin glass kind of behavior for the hydride. An upturn in the resistivity of HoCuH3 below 30 K may imply the presence of disorder, which is necessary for inducing spin glass behavior.