Sublattice magnetization in TbD2-crystalline electric field effects

The temperature dependence of the sublattice magnetization in Tb${\mathrm{D}}_2$ has been measured by neutron diffraction. A sharp increase in sublattice magnetization is observed at $T_N$. Calculations that take into account the combined effects of the molecular field and crystalline electric field have been performed. These calculations show that the sharp increase in sublattice magnetization is due to a first-order phase transition at $T_N$, which accounts for ∼0.3 of the saturated sublattice magnetization.