"MnAlN" is Really MnN.

We investigate the synthesis of antiperovskite "MnAlN" using the published synthesis procedure, as well as several new reaction pathways. In each case, only a combination of antiperovskite MnN and MnAl or precursors is obtained. The identity of the obtained antiperovskite phase is unambiguously determined to be MnN via synchrotron powder X-ray diffraction (SPXRD), X-ray absorption spectroscopy (XAS), and magnetometry. The experimental results are further supported by thermochemical calculations informed by density functional theory (DFT), which find MnAlN to be metastable versus decomposition into Mn and AlN. The DFT-based calculations also predict an antiferromagnetic ground state for MnAlN. This directly contradicts the previously reported ferromagnetic behavior of "MnAlN". Instead, the observed magnetic behavior is consistent with ferrimagnetic MnN. We examine the data in the original publication and conclude that the compound reported to be MnAlN is in fact MnN.