Er60Ni132: A new structure from the Ni occupied the 4b sites in cubic laves superstructure synthesized under high pressure and high temperature

Abstract

The title compound with structure derived from cubic laves was fabricated by the high pressure high temperature (HPHT) method. A new structure single crystal Er60Ni132 was discovered in the experiment. The single crystal X-ray diffraction result showed that the symmetry of Er60Ni132 was F-43m with a 2a*2a*2a unit cell. Its structure was derived from the original cubic laves ErNi2 whose symmetry was Fd-3m. In comparison to the Fd-3m structure, the doubling of the unit cell occurred due to the ordering of Ni atoms substituting the Er atoms in 4b sites. The formation energies of ErNi2 and Er60Ni132 were computed and investigated. With the cubic Laves structure, the title compound also showed good hydrogen storage properties.