ER-166 AND FE-57 MOSSBAUER-EFFECT IN ER2FE17NX

The Fe-57 Mossbauer effect in Er2Fe17N(x) was measured in the temperature range 4.2-580 K. The temperature dependence of the Fe-57 Mossbauer spectra shows a hyperfine field anomaly around the spin reorientation temperature (T(SR) almost-equal-to 110 K) where the easy magnetization direction changes from parallel to c (T < T(SR)) to perpendicular to c (T > T(SR)). The Er-166 Mossbauer spectrum of Er2Fe17N(x) was measured at 4.2 K. From the quadrupolar splitting it was determined that interstitial solution of N atoms strongly increases the second order crystal field coefficient (A2(0) almost-equal-to -400 K a0(-2)).