Fig. 2

Resistivity data showing the insulator–metal transition. a Resistivity plotted against temperature for V_0.9PS₃, for pressures ranging from ambient (blue, topmost) to 140 kbar (red, bottom). Above 112 kbar the resistivity transitions from an insulating temperature dependence to a metallic, decreasing with decreasing temperature. An estimate of the Mott–Ioffe–Regel limit, as discussed in the text, is shown as a dotted line, and clearly separates the insulating and metallic regimes. b Resistivity of V_0.9PS₃ at 140 kbar in the metallic state. Data at 124 kbar, close to the transition, are shown in the left inset. Right inset shows the low-temperature detail of the data at 124 kbar with a fit to a Kondo effect expression as a black dashed line