A spin glass state in Ba3TiRu2O9

The magnetic properties of Ba₃TiRu₂O₉, whose crystal structure is based on stacked triangular planar lattices of M₂O₉ dimers and single MO₆ octahedra, are reported. The system is magnetically disturbed by a substantial amount of Ti/Ru chemical disorder. The Weiss temperature and effective magnetic moment were found to be −29.5 K and 1.82 μ_B/f.u. respectively, and a bifurcation in the zero field cooled and field cooled magnetic susceptibility is observed below 4.7 K, suggesting that this is a compositionally-disordered spin-glass system. The material is a semiconductor with an activation energy for charge transport of approximately 0.14 eV.