We report on the X-ray absorption near edge structure (XANES) and X-ray magnetic circular dichroism (X-MCD) study of Nd₂TM₁₇A_x (TM=Co,Fe, A=N,H) materials for novel permanent magnets. Introducing N or H atoms onto interstitial sites increases the Curie temperature of iron compounds and a large increase of magnetocrystalline anisotropy can be achieved with N uptake. In order to study the influence of light elements on the electronic properties of individual elements, an X-MCD study on the Fe,Co:K edge as well as on the Nd:L_2,3 edges has been carried out. The XANES spectra on the Fe,Co:K edges show a smoothening of the middle-edge kink with H and N uptake. The effect is much stronger for the nitrides than for the hydrides and is attributed to a higher degree of localisation of Fe,Co 4p band, which is the final state of the K edge transition. The XANES spectra at the Nd:L_2,3 edges show a narrowing of the white line with H,N uptake. The effect is much stronger for the nitrides than for the hydrides and denotes a higher degree of localisation of the Nd 5d band which is the final state of the L_2,3 transitions. The normalised area of the white line for the nitrides is larger than in other compounds, which is attributed to a lower 5d band filling in the nitrides due to an electron transfer to adjacent nitrogen atoms. A decrease of magnitude of the negative K-edge X-MCD peak with H and N substitution in the cobalt compound is attributed to a decrease of polarization of the 4p band. A lowering of the positive X-MCD signal at the Nd:L₂ edge with N uptake denotes a lower spin polarization of 5d^3/2 band in Nd₂Co₁₇N_x. In iron-based compounds, the X-MCD spectra at Fe:K and Nd:L_2,3 edges do not show considerable changes with H or N addition. This can be interpreted as a weak influence of H and N atoms on the 4p and 5d electron polarization, possibly due to larger interatomic distances in the Fe compounds than in the Co compounds.

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