The structural, mechanical, electronic, and magnetic properties of Mn2-XFe1+XSi (X = 0, 0.25, 0.5, 0.75, 1) Heusler alloys were studied in the framework of the density functional theory (DFT). The results show that Mn2-XFe1+XSi compounds are mechanically and dynamically stable with Hg2CuTi type (X = 0, 0.25 and 0.5) and Cu2MnAl type (X = 0.75 and 1); the volume of the series compounds decreases and they can change from brittle to ductile as Fe content increases. All the compounds have half-metallic properties and their Fermi levels gradually move to the middle of the spin-down band gap as X increases. The magnetic moment of Mn2-XFe1+XSi mainly arises from more Mn-d orbitals than Fe-d orbitals and satisfies the extended Slater-Pauling rule; the energy gaps are generated from the split in the energy level of d-orbitals of atoms on A, C sites and then hybrid with the d-orbitals of atoms on B sites.

在密度泛函理论（DFT）的框架下研究了Mn2-XFe1 + XSi（X = 0、0.25、0.5、0.75、1）Heusler合金的结构，力学，电子和磁性。结果表明，Mn2-XFe1 + XSi化合物在Hg2CuTi型（X = 0、0.25和0.5）和Cu2MnAl型（X = 0.75和1）时具有机械和动态稳定性。随着铁含量的增加，系列化合物的体积减小，并且可以从脆性变为延性。所有化合物都具有半金属性质，并且随着X的增加，它们的费米能级逐渐移至自旋下降带隙的中间。Mn2-XFe1 + XSi的磁矩主要源于比Fe-d轨道更多的Mn-d轨道，并且满足扩展的Slater-Pauling规则。能隙是由原子在A的d轨道能级上的分裂产生的，