Anisotropic intermediate valence in Yb2M3Ga9 (M = Rh, Ir)

TL;DR

This study investigates the anisotropic intermediate valence behavior in Yb2M3Ga9 compounds, highlighting the role of crystal field and Anderson lattice effects through experimental measurements and theoretical modeling.

Contribution

It provides new insights into the valence fluctuations and magnetic properties of Yb2M3Ga9 using combined experimental and theoretical approaches.

Findings

Anisotropic magnetic susceptibility observed.

Temperature dependence of 4f occupation number characterized.

Crystal field effects are significant in these materials.

Abstract

The intermediate valence compounds Yb2M3Ga9 (M = Rh, Ir) exhibit an anisotropic magnetic susceptibility. We report measurements of the temperature dependence of the 4f occupation number, nf(T), for Yb2M3Ga9 as well as the magnetic inelastic neutron scattering spectrum Smag at 12 and 300 K for Yb2Rh3Ga9. Both nf(T) and Smag were calculated for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation. These results corroborate the importance of crystal field effects in these materials; they also suggest that Anderson lattice effects are important to the physics of Yb2M3Ga9.