Relief of spin frustration through magnetic anisotropy in the quasi-one-dimensional S = ? antiferromagnet Na2CuSO4Cl2

We report the magnetic structure and anisotropy of the quasi-one-dimensional S = 12 antiferromagnet Na2CuSO4Cl2 obtained by single-crystal neutron scattering, electron spin resonance (ESR), and magnetization measurements, following an earlier study of its dynamics [M. Fujihala etal., Phys. Rev. B 101, 024410 (2020)]. A Neel-type spin structure is formed within the chain of this compound, where the spins point along the b axis, and ESR data indicate an antisymmetric exchange with a uniform Dzyaloshinskii-Moriya (DM) vector pointing along the b axis. The anisotropy g factor and magnetic structure are strong indicators of magnetic anisotropy originating from a symmetric anisotropic exchange interaction and/or a magnetic dipole interaction. These results suggest that these terms of the anisotropic spin Hamiltonian counteract the effect of the DM interaction and stabilize the Neel-type structure in Na2CuSO4Cl2.

Automated summary

The magnetic structure and anisotropy of the quasi-one-dimensional S = 12 antiferromagnet Na2CuSO4Cl2 were studied, revealing the formation of a Néel-type spin structure. The anisotropy can be attributed to symmetric anisotropic exchange interaction and/or magnetic dipole interaction, which counteract the effect of the Dzyaloshinskii-Moriya interaction and stabilize the Néel-type structure in Na2CuSO4Cl2.