Anomalies in the elastic constants of antiferromagnetic uranium mononitride

Measured anomalies in the elastic constants of a single crystal of cubic anti-ferromagnetic uranium mononitride are reported. A dip of about 10% occurs in C₁₁ at 6 K below the Néel point $\text{T}{}_{\mathrm{<mtext>N</mtext>}}\text{?53}\text{K}$. Starting at T_N a renormalization in C₄₄ which is proportional to the square of the sublattice ,magnetization also occurs. The results are in general agreement with model calculations of the sound velocity renormalization due to spin-phonon interactions.