Field-independent features in the magnetization and specific heat of SM₃CO₄ge₁₃

The cubic intermetallic compound Sm₃Co₄Ge₁₃ (space group Pm3n) possesses a cage-like structure composed of Ge and displays an antiferromagnetic transition at T_N ≈ 6 K in magnetization, M(T), specific heat, C_p (T) and in thermal conductivity, κ(T). The magnetic transition at T_N is observed to be robust against applied magnetic fields up to 9 T. From the analysis of specific heat, a Sommerfeld coefficient γ = 80(2) mJ/mol-Sm K² is estimated. The magnetic entropy released at T_N is estimated as lower than that of a doublet, R ln(2). A positive Seebeck coefficient is observed for the thermopower, S(T). Photoemission spectroscopy reveals distinct electronic character of the near-E_F valence band states arising out of Co(3d)-Sm(4 f) hybridization and Sm(4 f) electron correlation. The unusual field-independent features in magnetization, specific heat and electrical transport is an indication of the significant correlation between f and d wave functions.