Dy5Ni0.66Bi2.34 and Lu5Ni0.56Sb2.44 – Substitution derivatives with the orthorhombic Yb5Sb3-type structure. Magnetocaloric effect of Dy5Ni0.66Bi2.34

Dy5Ni0.66Bi2.34 and Lu5Ni0.56Sb2.44 were synthesized by arc-melting and were found to adopt an orthorhombic Yb5Sb3-type structure. Cell parameters are a =12.075(2), b =9.165(2), c =8.072(1)Å for Dy5Ni0.66Bi2.34 and a =11.6187(9), b =8.933(1) and c =7.8377(6)Å for Lu5Ni0.56Sb2.44. Dy5Ni0.66Bi2.34 undergoes a step-like ferromagnetic transition around 66K. Magnetocaloric effect in terms of the magnetic entropy change, ΔS, reaches −3.73J/kgK at 75K for Dy5Ni0.66Bi2.34.