Electronic structure and magnetism in Ru-based perovskites

摘要: The magnetic properties of ruthenates with perovskite-derived structures, particularly ${(\mathrm{C}\mathrm{a},\mathrm{S}\mathrm{r})\mathrm{RuO}}_{3}$ and ${\mathrm{Sr}}_{2}{\mathrm{YRuO}}_{6}$, are studied within the context band-structure-based Stoner theory. First principles calculations used to demonstrate that in all cases correct behavior order can be obtained without recourse strong correlation effects insulating character ${\mathrm{Sr}}_{2}$${\mathrm{YRuO}}_{6}$ is reproduced. different states ${\mathrm{SrRuO}}_{3}$ ${\mathrm{CaRuO}}_{3}$ shown due structural distortions these materials, most significantly larger rotation octahedra Ca compound. found on verge a ferromagnetic instability, leading expectation giant local moments around impurities other anomalous analogy fcc Pd metal. Oxygen $2p$-derived hybridize strongly Ru $d$ three compounds, O, through this hybridization, plays an unusually large role properties. This involvement O responsible for magnetostructural coupling calculations. Transport analyzed using calculated Fermiology. Unusually magnon paramagnon couplings found, which consistent reported measurements low-temperature specific heat resistivity coefficient.