An ionothermally prepared S=1/2 vanadium oxyfluoride kagome lattice

Frustrated magnetic lattices offer the possibility of many exotic ground states that are of great fundamental importance. Of particular significance is the hunt for frustrated spin-1/2 networks as candidates for quantum spin liquids, which would have exciting and unusual magnetic properties at low temperatures. The few reported candidate materials have all been based on d⁹ ions. Here, we report the ionothermal synthesis of [NH₄]₂[C₇H₁₄N][V₇O₆F₁₈], an inorganic-organic hybrid solid that contains a S = 1/2 kagome network of d¹ V⁴⁺ ions. The compound exhibits a high degree of magnetic frustration, with significant antiferromagnetic interactions but no long-range magnetic order or spin-freezing above 2 K, and appears to be an excellent candidate for realizing a quantum spin liquid ground state in a spin-1/2 kagome network.