Publication at Faculty of Mathematics and Physics |
2009
Abstract
Occurrence of magnetic order on the basis of plutonium can be captured by ab-initio LDA U calculations. Systematic investigation of diverse Pu compounds reveals that the 5f occupancy plays a key role.
If the 5f states are populated by more than approx. 5.3 electrons, the Pu magnetism vanishes. For comparison with valence-band photoemission spectra, the Hubbard I method was used. It shows consistently higher 5f5 final state multiplet originating from the 5f6 admixture in the ground state for those compounds which are non-magnetic.
The 5f occupancy can reach 5.6-5.7 for Pu monochalcogenides. The data are strongly suggestive of analogy of Pu and valence fluctuators based on anomalous rare earths.