STRUCTURAL AND MAGNETIC CHARACTERISTICS OF THE INTERMETALLIC COMPOUNDS HO2NI17 AND ER2NI17

The intermetallic compounds Ho2Ni17 and Er2Ni17 crystallize in the hex agonal structure of Th2Ni17 with lattice parameters a = 8.32 angstrom, c = 8.03 angstrom and a = 8.28 angstrom, c = 8.03 angstrom respective ly. The compounds are ferrimagnetic and the effective magnetic moments per formula unit (fu) determined from the paramagnetic region are mu( eff)/fu = 16.51 mu(B) for Ho2Ni17 and mu(eff)/fu = 15.27 mu(B) for Er2 Ni17, very close to the theoretical values of 16.44 mu(B) and 15.16 mu (B). The critical Curie temperatures for the compounds are T(c) = 587 K (612 K after heat treatment) for Ho2Ni17 and T(c) = 572 K (605 K aft er heat treatment) for Er2Ni17.