Chemical properties and thermopower of the new series of skutterudite Ce/sub 1-p/Yb/sub p/Fe/sub 4/Sb/sub 12/

We report on sample preparation and electron microprobe analysis in the series Ce/sub 1-p/Yb/sub p/Fe/sub 4/Sb/sub 12/ that shows that a solid solution exists for all compositions in the series. As shown from X-ray absorption spectroscopy, Ce is trivalent throughout the series, whereas Yb valence linearly changes from 2.16 for Yb/sub 0.93/Fe/sub 4/Sb/sub 12.08/ to 2.71 for Ce/sub 0.85/Yb/sub 0.05/Fe/sub 4/Sb/sub 12.06/. The Seebeck coefficient is enhanced by more than 20% at room temperature in Ce-Yb mixed compounds as compared to CeFe/sub 4/Sb/sub 12/ or YbFe/sub 4/Sb/sub 12/.