First-principle calculation of electronic and optical properties of VO2 by GGA-1/2 quasiparticle approximation

Correctly elucidating the strong electron correlations of vanadium dioxide (VO2) is of great significance to understand the physics of the metal–insulator transition (MIT) and develop potential applications of VO2. Standard density functional theory is believed to be inappropriate to describe the MIT of VO2. Herein, the recently developed GGA-1/2 quasiparticle approximation is employed to perform first-calculations on VO2. The electronic structures of the metallic and insulating phases of VO2 are well described. The GGA-1/2 calculations indicate that the preferential occupancy of the d// orbitals leads to strong Mott–Hubbard correlation, which induces the splitting of the d// orbitals and the MIT of VO2. The calculations on electron energy-loss function reveal that the satellite electronic energy-loss spectroscopy peak of metallic phase VO2 is resulting from the plasma resonance. This work demonstrates that the GGA-1/2 approach facilitates the electron correlation calculations of VO2 and suggests that the strong Coulomb correlation is necessary to trigger the MIT.