Electrical properties and the metal-insulator transition in ${\left({\mathrm{Sc}}_x{\mathrm{Ti}}_{1-x}\right)}_2{\mathrm{O}}_3$

The resistivity, thermoelectric power, and lattice parameters of ${\mathrm{Ti}}_2$ ${\mathrm{O}}_3$ doped with varying amounts of scandium have been measured between 77 and 700 K. A metal-to-insulator transition has been encountered in all specimens between approximately 400 and 600 K. The magnitude of the transition is nearly independent of Sc doping up to 0.33 at.% and grows with further increase in Sc content of the specimens. The activation energy for conduction at first declines and then increases with increasing Sc content. Since Sc doping has no large effect on the transition temperature, it is concluded that the transition is largely lattice dominated.