Magnetic properties and cation site occupancy in Zn-substituted W-type hexagonal ferrites SrZnxMg2-xFe16O27

W-type ferrites are attractive as next-generation permanent magnets due to their stability and potential for high magnetization. We investigated SrZnxMg2-xFe16O27 using synchrotron XRD, neutron diffraction, and VSM. Rietveld refinements confirmed over 92.5% W-type phase and revealed clear site preferences: Zn2+ occupies down-spin 4etet(S) and 4ftet(S) sites, enhancing magnetization; Mg2+ favors the up-spin 6gocta(S–S) site, reducing magnetization. The excellent agreement among all measurements validates the analysis and suggests that displacing Fe3+ from the 4focta(R) site may further improve magnetization of W-type ferrites.