Abstract Crystal structure, magnetism, martensitic transition, electronic structure and mechanical properties of Heusler compounds Mg2YZ (Y = Sc, Ti, V, Z = Al, Ga, In) were studied by carrying out first-principles calculations based on density functional theory. All compounds in the cubic phase have an inverse Heusler structure with Hg2CuTi as the prototype. Mg2ScZ is paramagnetic and does not undergo a martensitic transition, while Mg2Ti(or V)Z undergoes a martensitic transition and shows ferromagnetism, which is basically unchanged (or smaller) with the phase transition. Y and Z atoms play major and minor roles, respectively, in the electronic structure, which directly affects the magnetism of the two phases. The calculated mechanical properties indicate that Mg2TiZ is ductile in the cubic phase and brittle in the tetragonal phase, while Mg2VZ has a similar brittleness in both the cubic and tetragonal phases. It is predicted that Mg2TiZ and Mg2VAl (or Ga) are prone to tetragonal distortion.

中文翻译：

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Heusler 合金 Mg2YZ（Y=Sc、Ti、V、Z=Al、Ga、In）中马氏体转变和磁性能的第一性原理研究

摘要 通过基于密度泛函理论的第一性原理计算，研究了Heusler化合物Mg2YZ (Y = Sc, Ti, V, Z = Al, Ga, In)的晶体结构、磁性、马氏体转变、电子结构和力学性能。立方相中的所有化合物都具有以 Hg2CuTi 为原型的反 Heusler 结构。Mg2ScZ是顺磁性的，不发生马氏体转变，而Mg2Ti(或V)Z发生马氏体转变并表现出铁磁性，与相变基本保持不变（或更小）。Y和Z原子分别在电子结构中起主要和次要作用，直接影响两相的磁性。计算的力学性能表明，Mg2TiZ在立方相中具有延展性，在四方相中则脆，而 Mg2VZ 在立方相和四方相中具有相似的脆性。据预测，Mg2TiZ 和 Mg2VAl（或 Ga）容易发生四方变形。