All-d-metal equiatomic quaternary Heusler hypothetical alloys ZnCdTMn (T = Fe, Ru, Os, Rh, Ir, Ni, Pd, Pt): A first-principle investigation of electronic structures, magnetism, and possible martensitic transformations

Abstract

A new series of Zinc-based all-d-metal equiatomic quaternary Heusler hypothetical alloys ZnCdTMn (T = Fe, Ru, Os, Rh, Ir, Ni, Pd, Pt) were designed, and their ground state, electronic structures, magnetism, and possible martensitic transformations, as well as the competition between the austenitic phase and the martensitic phase, were studied in this work. ZnCdTMn alloys have large magnetic moments, all larger than 3 µB, which mainly come from the Mn atom due to its strong exchange splitting. It is worth noting that the magnetic moment of ZnCdFeMn is quite considerable (Mt = 6.0202 μB), mainly due to the Mn and Fe atoms, both of which have large magnetic moments. Additionally, first-principles calculation indicated that the martensitic phase has a lower energy than the cubic phase; therefore, a possible martensitic transformation from cubic to tetragonal is likely to occur in ZnCdTMn. More importantly, the phase transformations can be tuned by the uniform strain. The energy difference ΔEM is defined as the difference in total energy between the martensitic and cubic states; a quite large value of ΔEM about 0.5 eV was discovered in ZnCdOsMn, compared with in other Heusler alloys. The ΔEM can also be regulated by the uniform strain. For different substances, the relationship between ΔEM and Vopt+X%Vopt for ZnCdTMn (T = Fe, Ru, Os, Rh) is different. We hope this work can provide guidance for researchers to further explore and study new spintronic and magnetic intelligent materials among all-d-metal Heusler alloys.