An x-ray diffraction study and calculation of the exchange interaction constant between the rare-earth sublattice and the 3d sublattice of Dy2Fe17-xAlx compounds

Aluminium-substituted Dy2Fe17-xAlx solid solution has been studied by step x-ray diffraction. A Rietveld analysis of the x-ray diffraction indicates that the Al atoms have a high initial affinity for the 18h site, show a high affinity for the 6c site and 1 8f site at high Al concentrations and are absent from the 9d site at all Al concentrations. The values of intersublattice magnetic coupling constant, J(R,T)/k, are calculated by the molecular field model according to the result of a Rietveld analysis of the x-ray diffraction.