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The measurements of the electrical resistivity ρ and the thermopower S of single crystal EuCo2P2 have been performed at temperatures from 1.5 to 300 K under hydrostatic pressures up to 3 GPa and in magnetic fields up to 10 T. The temperature dependences of ρ and S show drastic changes at a critical pressure Pc, which indicates a large modification of the electronic structure around the Fermi level due to the valence transition from Eu to Eu. In the low-pressure phase with magnetic Eu and nonmagnetic Co, the magnetic field dependences of ρ and S show sudden decrease at B ≈ 7 T, implying a metamagnetic transition. On the other hand, no drastic change in ρ(B) and S(B) curves is observed in the high-pressure phase with nonmagnetic Eu and magnetic Co.

Magnetic characteristics of a DyPd2Si2 single crystal with the ThCr2Si2-type structure have been studied from measurements of magnetic susceptibility (T) and magnetization M(B). It was found that DyPd2Si2 orders antiferromagnetically below TN = 9.2 K with the basal-plane [100] axis being the easy magnetization direction at high magnetic fields. Upon increasing magnetic field, the [100] magnetization curve exhibits at least six metamagnetic transitions at 0.2, 1.8, 3.0, 3.7, 4.2 and 6.1 T before reaching the saturation magnetization Ms = 10 B. Five metamagnetic transitions were detected on decreasing fields. For the [110] magnetization process, three metamagnetic transitions were evidenced. In contrast, the M(B) curve along the [001] axis, which is the hard magnetization direction, displays no metamagnetic transition; it shows a monotonous increase with a concave curvature up to 18 T. Finally, we constructed a comprehensive B100-T magnetic phase diagram consisting of six magnetic ordered phases.