Lattice and electronic properties of VO2 with the SCAN( plus U) approach

초록

Appropriate consideration of the electron correlation is essential to reproduce the intriguing metal-insulator transition accompanying the Peierls-type structural transition in VO(2)d. In the density functional theory-based approach, this depends on the choice of the exchange-correlation functional. Here, using a newly developed strongly constrained and appropriately norm (SCAN) functional, we investigate the lattice and electronic properties of the metallic rutile phase of VO 2 (R-VO 2) from the first-principles calculations. We also explored the role of the Coulomb correlation U. By adding U, we found that the phonon instability properly describes the Peierls-type distortions. The orbital-decomposed density of states presents the orbital selective behavior with the SCAN+U, which is susceptible to the one-dimensional Peierls distortion. Our results suggest that even with the SCAN functional, the explicit inclusion of the Coulomb interaction is necessary to describe the structural transition of VO2.

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