Systematic investigations of rare-earth ($R$)-based intermetallic materials are a leading strategy to reveal the underlying mechanisms governing a range of physical phenomena, such as the formation of a Kondo lattice and competing electronic and magnetic anisotropies. In this work, the magnetic, thermal, and transport properties of $R{\mathrm{Co}}_2{\mathrm{Al}}_8 (R=\mathrm{La},\mathrm{Ce},\mathrm{Pr},\mathrm{Nd}, \mathrm{and} \mathrm{Sm})$ single crystals are presented. ${\mathrm{LaCo}}_2{\mathrm{Al}}_8$ is characterized as a Pauli paramagnet, and transport measurements, with the current along and perpendicular to the orthorhombic $c$-axis (${\rho }_c$ and ${\rho }_{ab}$, respectively), reveal a clear electronic anisotropy, with ${\rho }_{ab}\approx (4$–$7){\rho }_c$ at $300\mathrm{K}$. We show that ${\mathrm{CeCo}}_2{\mathrm{Al}}_8$ is a Kondo lattice for which the Kondo coherence temperature $T_{\text{K}}^{*}$, deduced from broad maximums in ${\rho }_c$ and ${\rho }_{ab}$ at $\approx 68$ and 46 K, respectively, is also anisotropic. This finding is related to a possible underlying anisotropy of the Kondo coupling in ${\mathrm{CeCo}}_2{\mathrm{Al}}_8$. The Pr- and Nd-based materials present strong easy-axis anisotropy ($c$-axis) and antiferromagnetic (AFM) orders below $T=4.84$ and $8.1\mathrm{K}$, respectively. Metamagnetic transitions from this AFM to a spin-polarized paramagnetic phase state are investigated by isothermal magnetization measurements. The Sm-based compound is also an easy-axis AFM with a transition at $T=21.6\mathrm{K}$.

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• Kondo effect
• Magnetic anisotropy
• Magnetism
• Crystal growth
• Magnetization measurements
• Resistivity measurements
• Specific heat measurements
• Susceptibility measurements
• X-ray powder diffraction