The CeFe11Ti Permanent Magnet: A closer look at the microstructure of the compound

High-performance permanent magnets (PM) are based on compounds with outstanding intrinsic magnetic properties. Nowadays, the most powerful PMs are obtained from the favorable combination of rare earth metals (RE=Nd, Pr, Ce) with transition metals (TM=Fe, Co). Among them, CeFe11Ti is attracting considerable attention due to its large Curie temperature, magnetization, and magneto-crystalline anisotropy energy, in particular for the development of electric motors for future automatic electrification. In this work, we shed some light in the understanding of this important compound by performing periodic hybrid-exchange density functional theory (DFT) calculations. The electronic structure of the different steps in the formation of CeFe11Ti gives us a clear explanation on the effect of Ce and Ti on its magnetic properties. The latter plays a role in stabilizing the structure, while Ce significantly hybridizes with Fe orbitals and alters the electronic bands. The calculations are compatible with a valence of 3+ for Ce, which is crucial in order to obtain a large magneto-crystalline anisotropy. Several spin configurations have been analyzed, being the ferromagnetic one the most stable. The results presented here provide a powerful tool for the further development of optimized high-performance PMs.