We present bulk magnetic susceptibility, specific heat, transport, NMR, and NQR results of the perovskite compound ${\text{CaCu}}_3{\text{Ru}}_4{\text{O}}_{12}$. The data consistently describe a metallic state with a moderately enhanced Sommerfeld coefficient of $\gamma =92\text{mJ}/\text{mol}{\text{K}}^2$ and a spin-fluctuation temperature of about 180 K. The heat capacity below 2 K shows a logarithmic increase providing evidence for non-Fermi-liquid (NFL) behavior in ${\text{CaCu}}_3{\text{Ru}}_4{\text{O}}_{12}$. Further signatures of NFL properties are found in NQR measurements revealing deviations from a Korringa behavior of the spin-lattice relaxation rate. The results are discussed with respect to heavy-fermion and NFL properties in other transition-metal compounds and traditional $f$-electron systems.

• Received 24 July 2008

DOI:https://doi.org/10.1103/PhysRevB.78.165126