Ferromagnetic Ordering and Heavy Fermion Behaviour in Ce₂Ru₃Ge₅

We report the investigation of the magnetic susceptibility (χ), specific heat (C_P), electrical resistivity (ρ) and magnetoresistance (MR) studies of the compound Ce₂Ru₃Ge₅. Ce₂Ru₃Ge₅ crystallizes in U₂Co₃Si₅-type structure with space group of Ibam. The lattice parameter values were observed to be a = 9.9497(4) Å, b = 12.416(4) Å, c = 5.8978(2) Å. Employing χ(T), C_P(T), ρ(T), and MR measurements, we show that the system exhibits a ferromagnetic ordering below 7.9 K with localized Ce³⁺ ions. A strong influence of field-dependent χ(T), ρ(T) and reduced saturation moment (0.32 μ_B) suggest that the crystalline electric field (CEF) plays a role in forming the ground state properties. The splitting energies between the ground state and two excited doublets in the CEF scheme are Δ₁ = 541 K and Δ₂ = 1999 K. Heat capacity measurements and analysis indicate that the system belongs to a heavy-fermion ferromagnetic class of materials with γ = 85 mJ=mol K and Kondo temperature T_K ≈ 18.9 K. The temperature variation of the magnetic heat capacity and 4 f-electrical resistivity below T_C could be modelled using the ferromagnetic spin-wave expressions.