Europium impurity systems

Eu—N system. — EuN was prepared [240] by direct combination of europium metal and nitrogen at 800° C. Keemm and Winkelmann s preparation [241] involved heating (700°) a mixture of finely divided europium and KC1 (1 3) in a stream of NH3. EuN, like SmN and YbN possesses the NaCl type structure. The lattice constant of EuN is a = 5.014 A according to Klemm and Winkelmann [241], and a = 5.007 0.004 A according to Eick et al [240]. However, the preparation of Eick et al. contained some impurity, possibly as oxide. 

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