NdNiMg5, a new magnesium-rich phase with an unusual structural type.
The new intermetallic NdNiMg5 was discovered during the study of the Mg-rich part of the Mg-Nd-Ni system. It was synthetized by melting of the constituent elements in a sealed tantalum tube with subsequent annealing. Its structure was determined by X-ray diffraction on a single crystal. Crystal data: orthorhombic system, Cmcm, Z = 4, a = 4.4799(2) Å, b = 9.9827(3) Å, c = 13.7854(10) Å, d(calc) = 3.49 g·cm(-3). Its structure is made of infinite layers of Mg atoms that form blocks stacked along the c axis. These blocks, with a close-packed array of Mg atoms, are separated by infinite NiNd layers and connected through short Mg-Mg bonds. In the NiNd layer, the Ni and Nd atoms form an ordered graphite-type network. Antiferromagnetic ordering is observed with T(N) = 12 K, and the effective magnetic moment μeff is equal to 3.89(1) μB.
CNRS, Université de Bordeaux, ICMCB , 87 Avenue du Dr. A. Schweitzer, Pessac F-33608, France.
Bassem
B
Ourane
Etienne
E
Gaudin
Ridha
R
Zouari
Samuel
S
Couillaud
Jean-Louis
JL
Bobet