Magnetic interactions in LiCu²O²: Single-chain versus double-chain models

Rémi Maurice (1) , Abdul-Muizz Pradipto (1) , Coen de Graaf (2, 1, 3) , Ria Broer (1)

1 Zernike Institute for Advanced Materials
2 Departament de Química Física i Inorgànica
3 ICREA - Institució Catalana de Recerca i Estudis Avançats = Catalan Institution for Research and Advanced Studies

The possible origin of the spiral spin structure in multiferroic LiCu²O² is studied by calculating all relevant isotropic and anisotropic magnetic interactions in the material. The coupling constants are extracted from accurate ab initio quantum chemical calculations with an effective Hamiltonian theory. First, the anisotropic or Dzyaloshinskii-Moriya interactions are found to be negligible. Secondly, we obtain small isotropic interactions of the spin moments located on different chains, which classifies the material as a quasi-one-dimensional magnetic system. The intrachain isotropic interactions between nearest neighbors are relatively large and ferromagnetic, while second-neighbor interactions along the chain have antiferromagnetic character and are about half the magnitude of the former. This frustration leads to a spiral spin structure, which can be subjected to electric polarization.

Domaines: Chimie théorique et/ou physique

Rémi Maurice, Abdul-Muizz Pradipto, Coen de Graaf, Ria Broer. Magnetic interactions in LiCu²O²: Single-chain versus double-chain models. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2012, 86, pp.24411. ⟨10.1103/PhysRevB.86.024411⟩. ⟨in2p3-01631019⟩