Resonant X-ray scattering study was carried out to investigate an anomalous ordered state (TA = 6.5 K.) in the filled skutterudite PrFe4P12. At the Pr-LIII absorption edge, we observed resonant features in h + k + l = odd reflections, which are forbidden in the BCC structure above TA. Because these reflections contain the difference of anomalous scattering factor between two Pr atoms in the BCC unit cell, and the ordered state is attributed to the ordering of two different electronic states of Pr.
- Filled skutterudite
- Resonant X-ray scattering