Insulating state and the importance of the spin-orbit coupling in Ca$_3$CoRhO$_6$

Hua Wu; Z. Hu; D. I. Khomskii; L. H. Tjeng

doi:10.1103/PhysRevB.75.245118

paper

Insulating state and the importance of the spin-orbit coupling in Ca $_{3}$ CoRhO $_{6}$

arXiv:0705.4538 · doi:10.1103/PhysRevB.75.245118

Abstract

We have carried out a comparative theoretical study of the electronic structure of the novel one-dimensional Ca $_{3}$ CoRhO $_{6}$ and Ca $_{3}$ FeRhO $_{6}$ systems. The insulating antiferromagnetic state for the Ca $_{3}$ FeRhO $_{6}$ can be well explained by band structure calculations with the closed shell high-spin $d^{5}$ (Fe $^{3 +}$ ) and low-spin $t_{2 g}^{6}$ (Rh $^{3 +}$ ) configurations. We found for the Ca $_{3}$ CoRhO $_{6}$ that the Co has a strong tendency to be $d^{7}$ (Co $^{2 +}$ ) rather than $d^{6}$ (Co $^{3 +}$ ), and that there is an orbital degeneracy in the local Co electronic structure. We argue that it is the spin-orbit coupling which will lift this degeneracy thereby enabling local spin density approximation + Hubbard U (LSDA+U) band structure calculations to generate the band gap. We predict that the orbital contribution to the magnetic moment in Ca $_{3}$ CoRhO $_{6}$ is substantial, i.e. significantly larger than 1 $μ_{B}$ per formula unit. Moreover, we propose a model for the contrasting intra-chain magnetism in both materials.

arXiv comment7 pages, 4 figures, and 1 table

Insulating state and the importance of the spin-orbit coupling in Ca $_{3}$ CoRhO $_{6}$

Abstract

References in corpus (13)

Cited by in corpus (12)

Insulating state and the importance of the spin-orbit coupling in Ca3​CoRhO6​

Abstract

References in corpus (13)

Cited by in corpus (12)

Insulating state and the importance of the spin-orbit coupling in Ca $_{3}$ CoRhO $_{6}$