Magnetic Ordering of the Edge-Sharing CuO2Chains in Ca2Y2Cu5O10

Abstract
A neutron powder diffraction study revealed that Ca 2 Y 2 Cu 5 O 10 , which consists of edge-sharing CuO 2 chains, shows an antiferromagnetic long-range ordering below ∼29 K. The arrangement of the Cu 2+ spins is ferromagnetic along the chain ( a axis) with a spin direction along the b axis. The magnetic structure has the propagation vector k = [001] . The ordered moment of the Cu 2+ spins is ∼0.9 µ B at 10 K, suggesting that the interchain interactions are fairly large. The observed intensities can be better described by assuming an ordering of oxygen moments which are induced due to the strong hybridization between the copper and oxygen ions.