Abstract
From the resistivity and magnetic susceptibility measurements of polycrystalline BixV8O16 with 1.6<x<1.8, it was revealed for the first time that BixV8O16 with 1.72<x<1.8 exhibits a temperature-induced metal-insulator transition (MIT). A large hysteresis was observed in their susceptibilities and resistivities as functions of temperature, indicating that the MIT is of the first order. The possibility of charge ordering between V3+ and V4+ has been discussed for the origin of the MIT in this system. In the insulating phase, BixV8O16 with 1.72<x<1.8 indicates another anomaly in the magnetic susceptibility, which may imply magnetic ordering below the anomaly temperature. We suggest that the physical properties of this system are controlled by multiple order parameters including charge, spin, and orbital quanta.
