Structure and magnetic properties of the (Cr,T,Ni)₄Si phases, T = Fe, Ru, Pd

Chem. Met. Alloys 14 (2021) 31-37

https://doi.org/10.30970/cma14.0417

Romana-Iryna MARTYNIAK, Nataliya MUTS, Matej BOBNAR, Lev AKSELRUD, Roman GLADYSHEVSKII

The π phase (Cr,T,Ni)₄Si, where T is Fe, Ru, or Pd, crystallizing with an Au₄Al-type structure (Pearson symbol cP20, space group P2₁3), was synthesized in three alloys of the Cr₂₆Fe₉Ni₄₇Si₁₈, Cr₂₆Ru₉Ni₄₇Si₁₈, and Cr₂₆Pd₉Ni₄₇Si₁₈ nominal compositions. The crystal structures of the (Cr,T,Ni)₄Si phases were refined from X‑ray powder diffraction data: cell parameter a = 0.612574(9) nm for (Cr_0.32Fe_0.11Ni_0.57)₄Si; a = 0.614454(8) nm for (Cr_0.40Ru_0.08Ni_0.52)₄Si; a = 0.61831(1) nm for (Cr_0.33Pd_0.11Ni_0.56)₄Si. The temperature dependence of the magnetic susceptibility of the (Cr_0.40Ru_0.08Ni_0.52)₄Si compound was studied in external magnetic fields of up to 7 T and in the temperature range between 1.8 and 350 K. The Cr₂₆Ru₉Ni₄₇Si₁₈ alloy exhibits paramagnetic behavior governed by the modified Curie-Weiss law: χ₀ = 172.7·10^-6 emu g-at^-1; C = 3.7·10^-3 emu g-at^-1 K^-1; Θ_p = -34 K.

Projection of the structure of (Cr_0.40Ru_0.08Ni_0.52)₄Si along [001] and coordination polyhedra of the three sites.

Keywords

X-ray powder diffraction / Crystal structure / βMn structure type family / Magnetic properties / Magnetic skyrmions