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The magnetic properties of the solid solutions URu1−xPdxGe with x = 0.1 0.9, crystallizing in the orthorhombic TiNiSi-type structure, were investigated by ac magnetic susceptibility and dc magnetization measurements. The experimental data reveal that there are three dierent regions of magnetic behaviour. A nonmagnetic ground state occurs for x < 0.3, however, as the Pd concentration is increased, the antiferromagnetism is stabilized for x = 0.35 0.8, and two successive transitions, antiferro-and ferromagnetic, emerge in the x = 0.9 composition.

We report the measurements of dc-magnetization (M), specic heat (Cp) and electrical resistivity (ρ) of an intermetallic URu0.68Pd0.32Ge, that lies at the border between nonmagnetic and magnetic regimes in the magnetic phase diagram of solid solutions URu1−xPdxGe. The studied composition shows enhanced dc-magnetic susceptibility χ(T ) and the Sommerfeld ratio Cp(T )/T at low temperatures. Below 4 K χ(T ), Cp(T )/T and ρ(T ) can be described by χ(T ) ∝ T −0.48 , Cp(T )/T ∝ √ T and ρ(T ) ∝ c ln(T ) + AT 3/2 , respectively. These observations provide an evidence that URu0.68Pd0.32Ge is a moderately heavy-fermion system with an electronic ground state of non-Fermi liquid character. We found non-linear eect of the magnetization and a large value of the Wilson ratio, which are consistent with the interpretation in terms of magnetic instability.

We report the measurements of thermoelectric power, S(T ), of the URu1−xPdxGe solid solutions in the temperature range 1.9300 K. It is found that S(T ) of URuGe is consistent with the behaviour of Kondo lattice, characterized by a low-temperature negative minimum and a high-temperature positive maximum. On the contrary, S(T ) of the compositions 0.1 ≤ x ≤ 0.7 is negative over the whole temperature range measured and shows only one negative minimum around 200 K. The compositions x = 0.9 and 1, in addition to a high-temperature negative minimum, exhibit anomalies at low temperatures, presumably associated with the magnon drag. We interpret the experimental data assuming the presence of the Kondo and crystal-electric eld eects.