Sm2Fe17N x : Site and valence of the interstitial nitrogen

X-ray absorption fine structure from the samarium L3 edge reveals that there are 2.8±1.0 nitrogen atoms in Sm2Fe17Nx covalently bonded 2.54 Å from the Sm site. This coordination number and radial distance are consistent with N atoms occupying the 9(e) sites of the expanded Sm2Fe17 lattice.