TABLE III: Energy of the 3 Kramer’s doublets after CF splitting of the degenerated ground state J = 5/2 multiplet. FIG. 1: (Color online) Temperature dependence of specific heat measured in various magnetic fields applied parallel to the c -axis. The inset shows details of the low-temperature anomalies. 16 Levels Energy [K] Δ$_{1}$ 0 Δ$_{2}$ 130 ± 15 Δ$_{3}$ 300 ± 40