We present PAC measurements performed using the 172Yb probe in two Yb intermetallic compounds, Yb4As3 and Yb5Si3. The hyperfine quadrupole interaction was measured in a wide temperature range from 78 to 850 K. The temperature dependence of the electric field gradient differentiates divalent and trivalent Yb ions. In Yb4As3 we observe a phase transition at 295 K and a heterogeneous mixed valence state in the low temperature phase. By contrast, the Yb ions in the two crystallographic sites in Yb5Si3 can be classified as trivalent Yb ions with a large crystal field interaction.
- Electric field gradient
- Perturbed angular correlation spectroscopy
- Valence states
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering