We report our results on two new ternary intermetallic compounds Pr_2Pd_3Ge_5 and Pr_2Rh_3Ge_5 based on magnetic susceptibility, magnetization, specific heat, resistivity and magnetoresistance data. These compounds form in U_2Co_3Si_5-type orthorhombic structure (space group Ibam). Pr_2Pd_3Ge_5 exhibits two magnetic transitions at T_N1 = 7.5 K and T_N2 = 8.3 K. In the magnetically ordered state Pr_2Pd_3Ge_5 exhibits a field induced metamagnetic transition and unusually large magnetoresistance.

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... r_2Rh_3Ge_5 does not show any phase transition down to 0.5 K. It has a CEF singlet ground state, separated from the first excited state by about 10 K. The low lying crystal field excitations lead to exciton mediated electronic mass enhancement as evidenced by large Sommerfeld coefficient (γ ∼ 80 mJ/mol K^2) in Pr_2Rh_3Ge_5.