Hole dopants disentangling Peierls−Mott relevance states of VO₂ by first-principles calculation

The formation mechanism of the metastable M₂phase VO₂, which is believed to be a true Mott insulator, has attracted great attention for understanding the intriguing physics of the metal−insulator transition of VO₂ and the promising application in ultrafast electronic switching devices. Herein, we conducted the hole-doping calculation regardless of the type of element and revealed theoretically that the hole carriers disentangle the complex Mott−Peierls relevance states of M₁phase VO₂. The hole induces the zigzag dimerized V−V chains to separate into two different states: one remains paired but straight and the other remains zigzag but unpaired. The dedimerization weakens the intradimer hopping, which makes the superexchange interaction come into effect, consequently resulting in the formation of the spin antiferromagnetic ordering along the zigzag unpaired V−V chains, indicating that the Mott correlation plays a dominant role in the formation of M₂-VO₂. This work gives an insight into the mechanism of stabilizing the “true” Mott insulator M₂-VO₂, which would offer an opportunity for the realization of Mott transition field-effect transistors.