Investigations on Structural, Stability, and Magnetic Properties of Zr 4 Mn 4 Si 7

Ternary intermetallic silicides, germanides, and stannides of 4‐4‐7 stoichiometry are known to crystallize in the Zr 4 Co 4 Ge 7 ‐type structure of space group I4/mmm . A distinctive feature of this type of structure lies in the presence of short Si–Si, Ge–Ge, and Sn–Sn interatomic distances, close to the covalent bonding distances in the diamond‐type structures of silicon, germanium, and tin, which are thought to promote the emergence of remarkable physical properties. In this article, experimental and theoretical investigations performed on Zr 4 Mn 4 Si 7 are reported and discussed. It is shown that this compound, in its stoichiometric composition, crystallizes in an unprecedented crystal structure of space group P4/nmm , strongly related to the Zr 4 Co 4 Ge 7 ‐type. Theoretical calculations based on density functional theory and combined with the experimental results show that silicon deficiency in nominal composition and temperature are key parameters in its phase stability. Finally, magnetic measurements reveal a ferromagnetic‐like phase transition around 45 K.