Crystal and magnetic structure of polar oxide HoCrWO6

Polar magnetic oxide HoCrWO6 is synthesized and its crystal structure, magnetic structure, and thermodynamic properties are investigated. HoCrWO6 forms the polar crystal structure (space group Pna2(1) (#33)) due to the cation ordering of W6+ and Cr3+. There is an antiferromagnetic transition at T-N = 24.5 K along with the magnetic entropy change (similar to 5 J.Kg.K--1(-1) at 70 kOe). Neutron diffraction measurement indicates that both Cr and Ho sublattices are ordered with the moment of 2.32(5)mu(B) and 8.7(4)mu(B) at 2 K, respectively. While Cr forms A-type collinear antiferromagnetic (AFM) structure with magnetic moment along the b axis, Ho sublattice orders in a non-coplanar AFM arrangement. A comparison with isostructural DyFeWO6 and DyCrWO6 indicates that the magnetic structure of this family of compounds is controlled by the presence or absence of e(g) electrons in the transition metal sublattice.