ChemInform Abstract: Effect of Interstitial Hydrogen and Nitrogen on Magnetic and Structural Properties of R2T17 (R: Y, Ce and Sm; T: Fe, Co and Ni).

Abstract

1995 dielectric properties, magnetic properties dielectric properties, magnetic properties D 9000 -012Effect of Interstitial Hydrogen and Nitrogen on Magnetic and Structural Properties of R2T17 (R: Y, Ce and Sm; T: Fe, Co and Ni). -The title effects are investigated by XRD and magnetic measurements of R2T17 hydrides and nitrides. The saturation moment, Ms of Y2Fe17Ny compounds increases from 34.0 µB at y = 0 to 39.7 µB for y = 3.1 while that of the hydrides Y2Fe17Hx decreases from 34.0 to 32.8 µB for x = 2.9 and recovers to 34.4 µB for x = 4.6. The Curie temp., Tc, increases from 300 to 701 K upon nitrogenation and to 481 K for an H uptake of x = 2.9. For Y2Co17 hydrogenation and nitrogenation lead to a significant decrease of both Ms and Tc and Y2Ni17 loses its ferromagnetism upon hydrogenation and becomes paramagnetic even at 4.2 K. Conversion to ferromagnetism upon nitrogenation and hydrogenation of Ce2Fe17 is attributed to the decrease in the hybridization between Ce 4f and Fe 3d electron states by lattice expansion. -(FUJII, H.; AKAYAMA, M.; NAKAO, K.; TATAMI, K.; J. Alloys Compd. 219 (1995) 10-15; Fac. Integr. Arts Sci., Univ., Higashi-Hiroshima 724, Japan; EN)

Ab-initio study of the electronic structure and magnetic properties of Ce$_2$Fe$_{17}$

“…This change in the 4f electron character as the effect of interstitial hydrogen and nitrogen is also described in Ref. [22].…”

“…The calculated atom projected magnetic moments for this calculation are: 2.64 for the Fe 6c site, 2.20-2. 22 for the Fe 9d site, 2.46-2.49 for the Fe 18f site, 2.41-2. 44 for the Fe 18h site, and -0.31 for the Ce 6c site.…”

“…Furthermore, the 4f electron character might change as the effect of doping [22,23,24,2,20,25] (for the details see Appendix A). It is shown that a considerable increase in volume, magnetization, and T is observed along with the decrease in Ce valence i.e.…”