Interchain interactions of Li2CuO2 probed by 7Li NMR

Li-7 NMR study was performed on polycrystalline Li2CuO2, which has edge-sharing chains of CuO4 squares. The Knight shift and the nuclear spin lattice relaxation time in the paramagnetic state and the spectrum in the antiferromagnetic state below T-N ( similar or equal to 9 K) are reported. The Li-7 NMR results are consistent with dominant interchain interactions through oxygen and lithium atoms, which is responsible for the antiferromagnetic ordering of this compound. The internal field observed at the Li site below T-N is small and comparable to the lattice dipolar field calculated for the antiferromagnetic spin structure proposed from neutron diffraction results. (C) 2001 Elsevier Science B.V. All rights reserved.