Non-one-dimensional behavior in charge-ordered structurally quasi-one-dimensional Sr6Co5O15

Abstract

We have synthesized Sr6Co5O15, a quasi-one-dimensional oxide, measured its magnetic properties, and calculated its electronic structure by ab initio techniques. We have found strong evidence for its electronic and magnetic behavior not to follow the trend of its structural series. The magnetic coupling inside the CoO3 chains is not purely ferromagnetic, and the long-range coupling inside the chains is very weak. The Co moments are slightly canted due to their large orbital angular momenta being oriented along each particular quantization axis, which is different for each Co4+ atom in the structure. Our thermopower calculations are in agreement with the experiment, supporting our model of the magnetic ground state of the compound.