Single Crystal Growth and Magnetic Properties of Antiferromagnet Ce₂Pd₃Si₅

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We succeeded in growing a single crystal of Ce₂Pd₃Si₅ with the orthorhombic crystal structure by the Sn-flux method and measured the electrical resistivity, specific heat, magnetic susceptibility and magnetization. The antiferromagnetic ordering was confirmed to occure below T_N=7.2 K. The electronic specific heat coefficient was determined as 77 mJ/(K²·mol·Ce). The antiferromagnetic easy-axis was found to be the [001] direction, with an ordered moment of μ_s=1.3 μ_B/Ce, while [100] and [010] directions are hard-axes in magnetization. We observed a metamagnetic transition at H_c=5.7 T for H||[001] and a saturation of magnetization above H_s=12.1 T. The characteristic magnetic phase diagram was constructed. The crystalline electric field (CEF) scheme was also proposed for Ce₂Pd₃Si₅, where the splitting energies between the ground state and two excited doublets in the CEF scheme are estimated to be 87 and 504 K, respectively.