CeRhSn is a valence fluctuating heavy-fermion metal with a twisted Ce-kagome lattice, displaying zero-field quantum criticality, previously associated with geometrical frustration. The partial substitution of Rh by Pd in ${\mathrm{CeRh}}_{1-x}{\mathrm{Pd}}_x\mathrm{Sn}$ enlarges the unit-cell volume, suppresses valence fluctuations, decreases the Kondo temperature, and stabilizes a possible long-range antiferromagnetic (AFM) ordered ground state with $T_N=0.8$ K at $x=0.5$. Previous thermodynamic and spectroscopic measurements for $x=0.1$ suggested a quantum critical spin liquid. We report low-temperature dilatometry and magnetization measurements on ${\mathrm{CeRh}}_{0.9}{\mathrm{Pd}}_{0.1}\mathrm{Sn}$ and compare with published low-$T$ specific heat data. The absence of a Grüneisen parameter divergence excludes a conventional quantum criticality scenario. Instead, the weak power-law divergences signal non-Fermi-liquid (NFL) behavior, according to a disorder-driven quantum Griffiths phase scenario. At low temperatures, a negative thermal expansion is found in fields above approximately 0.5 T and the NFL scaling breaks down, probably due to the polarization of AFM correlations.

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• Frustrated magnetism
• Kondo effect
• Quantum criticality
• Thermal expansion
• Disordered systems
• Heavy-fermion systems
• Magnetization measurements
• Thermodilatometry