Hydrogen absorption and magnetic properties of intermetallic compounds based on 3d elements
A review is given of the various types of changes in magnetic properties due to hydrogen absorption observed in certain groups of intermetallic compounds. These comprise compounds of 3d transition metals in which the second component is one of the strongly hydrogen attracting metals such as Ca, Y, the rare earths, Sc, Ti, Zr, Hf or Th. The changes in magnetic properties do not only entail increases or decreases in transition metal moment but also changes from Pauli paramagnetism to ferromagnetism as well as changes in the reverse direction. It is dis— cussed to what extent these changes can be explained in terms of changes in 3d band occupation and changes in 3d band exchange splitting. Particular attention is given to the changes in 5TFe isomer shift observed in several Fe compounds.