  Here, we report on the structural, electronic, and magnetic properties of a
polycrystalline sample of the LaCaCoIrO$_6$ double-perovskite investigated by
means of synchrotron x-ray powder diffraction, x-ray absorption spectroscopy,
and x-ray magnetic circular dichroism at the Co and Ir $L_{2,3}$ edges,
magnetometry, and electrical transport. Our results indicate a configuration of
nearly Co$^{2+}$/Ir$^{5+}$ configuration for the transition-metal ions, with
spin canting within the Co antiferromagnetic superstructure responsible for the
ferromagnetic-like behavior observed below 100 K. The highly insulating
character of LaCaCoIrO$_6$ and its positive magnetoresistance further suggest
that this antiferromagnetic superexchange interaction occurs through an
indirect hybridization between the Co $e_g$ orbitals

Strongly Correlated Electrons;Materials Science