| Popis: |
A free energy model is presented, which describes qualitatively the insulator-metal transition in Ti 2 O 3 and the high temperature transition in V 2 O 3 . The free energy description includes band electron entropy, and elastic and electron-electron energies. The transition in both cases is due to band-crossing effects, driven mainly by competition between electron-electron energy and band electron entropy. The model gives a good qualitative description of the transition in Ti 2 O 3 , and changes produced by addition of a few percent vanadium. Application to V 2 O 3 gives a good qualitative description of the high temperature transition from metal to a poorer conductivity metal, and a qualitative description of the changes produced by a few percent of chromium. |
