Direct Experimental Evidence of Toroidal Symmetry in the Lanthanum-based Molecular Magnet Dy₈

(Et₄N)₄[Dy₈O(nd)₈(NO₃)₁₀(H₂O)₂]₂MeCN (Dy₈) [1] is an intramolecular coupled lanthanide molecule with a Christmas star-like shape. Fits by an Ising type exchange Hamiltonian to low-temperature measurements of the angular dependence of the magnetization provide direct evidence of toroidal symmetry of the magnetic moments in this molecular nanomagnet. This experimental spin configuration result is consistent with the single ion easy axes, which are determined by an electrostatic crystal field point charge model. The short length scale for the decay of stray magnetic fields of toroidal qubits qualifies Dy₈ as an excellent potential candidate for data storage and/or quantum computation. [1] D. I. Alexandropoulos, et al., Inorg. Chem. 53, 5420 (2014).