Role of van der Waals forces in the metal-insulator transition of transition metal oxides.

Transition metal oxides (TMOs) exhibit great potential in technological applications due to their ability to undergo a rapid metal-insulator transition (MIT). However, the phase stability of TMOs, which models the on/off voltages of electronic devices, remains controversial due to the incomplete knowledge of the determinants of its stability. Herein, we study the effect of van der Waals (vdW) interactions on the phase stability of TMOs by employing the pairwise and screened vdW methods. Our calculations manifest that the vdW interactions are crucial to the TMOs' phase stability and tend to stabilize the insulating phase. Furthermore, the long-range electrodynamic screening interactions correct the TMOs' phase stability by revising the vdW term.