Influence of Barium Intercalated Ions on Magnetic Interaction in the Tellurate Compound BaNi 2 TeO 6 .

A novel transition metal tellurate single-crystal BaNi 2 TeO 6 with layered honeycomb lattices has been successfully synthesized. The crystal structure of BaNi 2 TeO 6 reveals that there are the Ni 2+ honeycomb lattice layers and Te 6+ triangle lattice layers in the ab plane. BaNi 2 TeO 6 shows an antiferromagnetic (AFM) transition at ∼25 K, which is almost the same temperature as the Curie-Weiss temperature θ ∼ -27 K, indicating the presence of the AFM interactions without obvious magnetic frustration in the system. However, the field-induced successive magnetic transitions observed at H c1 ∼ 16.2 T and H c2 ∼ 42.2 T show the complicated spin structure in BaNi 2 TeO 6 . Compared with the isostructural Na 2 Ni 2 TeO 6 , the various magnetic properties indicate that the intercalated ions (Ba 2+ ) can significantly affect the magnetic properties of the layered honeycomb lattices, which may be useful for exploring the spin-liquid state and valence bond liquid state in the layered honeycomb lattice compounds.