Magnetic structure and magnetoelectric effect in the centrosymmetric antiferromagnet Cu2(MoO4)(SeO3)

Magnetic properties of Cu2(MoO4)(SeO3), an S = 12 centrosymmetric antiferromagnet (AFM), were investigated using superconducting quantum interference device magnetometry, neutron diffraction, and magnetoelectric (ME) measurements. The magnetic susceptibility measurements indicate a broad peak at ∼50 K, followed by a phase transition into AFM order at TN=23.6(1) K. Above TN, a fit to the Curie-Weiss law gives a Curie-Weiss temperature ΘCW=-68(1) K, suggesting the dominant AFM coupling. Neutron powder diffraction reveals that the Cu2+ spins are aligned AFM along the c axis with weak noncollinearity under the magnetic space group of P21′/c. The ME response indicates that a nondiagonal component of a ME tensor is active, supporting the simultaneous spatial and time reversal symmetry breaking under P21′/c.