Electronic structure and thermoelectric properties of CuRh 1 − x Mg x O 2

Antoine Maignan (1) , Volker Eyert (2, 1) , Christine Martin (1) , Stefan Kremer (1, 3) , Raymond Fresard (1) , Denis Pelloquin (1)

1 CRISMAT - Laboratoire de cristallographie et sciences des matériaux
2 Center for Electronic Correlations and Magnetism
3 Institut fur Theorie der Kondensierten Materie

Electronic structure calculations using the augmented spherical wave method have been performed for CuRhO2. For this semiconductor crystallizing in the delafossite structure, it is found that the valence-band maximum is mainly due to the 4d t2g orbitals of Rh3+. The structural characterizations of CuRh1−xMgxO2 show a broad range of Mg2+ substitution for Rh3+ in this series, up to about 12%. Measurements of the resistivity and thermopower of the doped systems show a Fermi-liquidlike behavior for temperatures up to about 1000 K, resulting in a large weakly temperature-dependent power factor. The thermopower is discussed both within the Boltzmann equation approach as based on the electronic structure calculations and the temperature-independent correlation functions ratio approximation as based on the Kubo formalism.

Domaines: Matériaux

Antoine Maignan, Volker Eyert, Christine Martin, Stefan Kremer, Raymond Fresard, et al.. Electronic structure and thermoelectric properties of CuRh 1 − x Mg x O 2. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2009, 80 (11), ⟨10.1103/PhysRevB.80.115103⟩. ⟨hal-02264093⟩