Commensurate antiferromagnetism in CePt 2 In 7 , a nearly two-dimensional heavy fermion system

${\text{CePt}}_{2}{\text{In}}_{7}$ is a new heavy fermion system with a structure similar to the $\text{Ce}M{\text{In}}_{5}$ system but with greater two-dimensional character. We report the synthesis and characterization of phase pure polycrystalline material, which reveals an antiferromagnetic transition at ${T}_{N}=5.2\text{ }\text{K}$. Nuclear quadrupolar resonance studies indicate that the antiferromagnetism is commensurate and exhibits strong antiferromagnetic fluctuations in the paramagnetic state.