XAFS Study of the Ce Valence in Magnetic Ce Intermetallic Compounds

摘要

We report on the XAFS analysis of the valence state of Ce in intermetallic compounds whose structure is of ThMn 12 type. Ce is known to exhibit different valence state in intermetallic phases. Here we focus on iron-based Ce compounds, known for their prospective magnetic properties. We have studied the influence ofiron substitution by non magnetic elements such as Ti, Ga, Al on the electronic state of cerium. The Ce L3 absorption edge XAFS is measured using the DCI synchrotron radiation facility at LURE. The spectra are discussed in terms of the change in the Ce valence as the result of progressive substitution of iron. The main magnetic properties are briefly presented.