Optimizing <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si7.svg" display="inline" id="d1e680"> <mml:msup> <mml:mrow> <mml:mi>α</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>′</mml:mo> <mml:mo>′</mml:mo> </mml:mrow> </mml:msup> </mml:mat

Based on systematic first-principles calculations, we investigate the effects of 27 alloying elements on the intrinsic magnetic properties of α ′ ′ -Fe 16 N 2 , in order to further optimize its properties for permanent magnet applications. Analysis on the thermodynamic stabilities based on formation energy and distance to the convex hull reveals that 20 elements can be substituted into Fe 16 N 2 , where there is no strong site-preference upon doping. It is observed that all alloying elements can essentially reduce the saturation magnetization, whereas the magnetic anisotropy can be significantly modified. In terms of the Boltzmann- average intrinsic properties, we identify 8 elements as interesting candidates, with Co, Mo, and W as the most promising cases for further experimental validations. • High-throughput DFT screens 27 alloying elements for α ′ ′ -Fe 16 N 2 permanent magnets. • Eight dopants enlarge MAE; Co, Mo, W yield 1.9–2.4 MJ m −3 at room temperature. • Reveals stability–anisotropy trade-off and delivers rare-earth-free design rules.