Explore stable ternary regular Heusler alloys via high-throughput first-principles calculations
We carried out comprehensive first-principles calculations for 27,865 compositions of ternary ordered Heusler alloys and constructed the largest-ever comprehensive Heusler alloy database. The main achievements are summarized as follows. (Xiao & Tadano, 2025)
Using the supercomputer Fugaku, we performed exhaustive phonon calculations and precisely evaluated crystal stability by explicitly accounting for phonon stability, which had often been overlooked in previous studies. As a result, we identified approximately 4,000 compositions with high stability. Furthermore, by classifying each composition according to its constituent elements X, Y, and Z into three categories:(i) thermodynamically unstable, (ii) thermodynamically stable but phonon unstable, and (iii) stable with respect to both thermodynamics and phonons.
The comprehensive calculations revealed that ordered Heusler alloys with the X2YZ composition (regular or inverse structures) tend to exhibit higher stability when the Z atom has a smaller first ionization energy and atomic radius. In contrast, for half-Heusler alloys with the XYZ composition, the atomic radius of the Y atom plays a more critical role than that of the X atom. We demonstrated that 94% of stable half-Heusler alloys satisfy the condition that the atomic radius of Y is larger than that of X.
We also systematically calculated Curie and Néel temperatures and identified approximately 600 compositions that exhibit magnetic transition temperatures above room temperature while maintaining high crystal stability. Among these, 47 candidates were identified as compensated ferrimagnets with nearly zero net magnetic moment. For these candidates, we further discovered 12 and 8 materials exhibiting large anomalous Hall and anomalous Nernst effects, respectively.
Using the supercomputer Fugaku, we performed exhaustive phonon calculations and precisely evaluated crystal stability by explicitly accounting for phonon stability, which had often been overlooked in previous studies. As a result, we identified approximately 4,000 compositions with high stability. Furthermore, by classifying each composition according to its constituent elements X, Y, and Z into three categories:(i) thermodynamically unstable, (ii) thermodynamically stable but phonon unstable, and (iii) stable with respect to both thermodynamics and phonons.
The comprehensive calculations revealed that ordered Heusler alloys with the X2YZ composition (regular or inverse structures) tend to exhibit higher stability when the Z atom has a smaller first ionization energy and atomic radius. In contrast, for half-Heusler alloys with the XYZ composition, the atomic radius of the Y atom plays a more critical role than that of the X atom. We demonstrated that 94% of stable half-Heusler alloys satisfy the condition that the atomic radius of Y is larger than that of X.
We also systematically calculated Curie and Néel temperatures and identified approximately 600 compositions that exhibit magnetic transition temperatures above room temperature while maintaining high crystal stability. Among these, 47 candidates were identified as compensated ferrimagnets with nearly zero net magnetic moment. For these candidates, we further discovered 12 and 8 materials exhibiting large anomalous Hall and anomalous Nernst effects, respectively.
