A new ternary arsenide Eu20Ni42As31: Preparation, crystal structure and physical properties

We have investigated the crystal structure, magnetic and electrical transport properties of the new ternary compound Eu20Ni42As31, crystallizing in the hexagonal Sm20Ni42P31 structure type, space group P63/m, a = 21.1496(7), c = 4.0734(2) Å, according to X-ray powder diffraction. From magnetic investigations it is evidenced that in this compound the europium is divalent, Eu2+. The compound orders antiferromagnetically at a Neèl temperature TN = 5 K. However, in moderate magnetic fields an overall ferromagnetic-like magnetization is observed. The measurements of the electrical resistivity prove this magnetic behaviour as well as the metallic character of the compound Eu20Ni42As31.