Metal-insulator Transition in Transition Metal Oxides

The metal-insulator transition in the V
2
O
3
system is discussed. A recent series of experiments on V
2
O
3
and (V
1−x
Cr
x
)
2
O
3
is reviewed. The phase diagram for the system is described. The Cr-doped mixed oxides are insulating at room temperature for x ≥ 0.009 and transform to a metal with the application of pressure. This phase transition is identified as a Mott transition. A comparison is made between the experimental results and theoretical predictions of the Mott transition.