Critical Assessment of the DFT + U Approach for the Prediction of Vanadium Dioxide Properties

Abstract

In a previous study (Stahl and Bredow, Chem. Phys. Lett. 2018, 695, 28–33), we have studied structural, energetic, and electronic properties of two vanadium dioxide VO2 polymorphs with modified global and range‐separated hybrid functionals. Since hybrid methods are computationally demanding, we evaluate the computationally more efficient DFT + U method in the present study. We assessed the widely used Dudarev PBE + U approach with a literature value of the effective Hubbard parameter Ueff = 3.4 eV. We compared the PBE + U results for the two VO2 polymorphs with our previous results, a self‐consistent hybrid functional sc‐PBE0, and the meta‐GGA functional SCAN. It was found that the PBE + U method yields a strongly distorted monoclinic phase and does not reproduce the metal‐to‐insulator transition of VO2 correctly, even with modified values of Ueff. On the other hand, sc‐PBE0 and SCAN describe the relative stability and the electronic structure of both polymorphs correctly and also provide reasonable lattice parameters. The functional SCAN yields the optimal balance between computational efficiency and accuracy. © 2019 The Authors. Journal of Computational Chemistry published by Wiley Periodicals, Inc.

Surfaces of VO2‐Polymorphs: Structure, Stability and the Effect of Doping

“…In a previous study [29] we found that a self‐consistent hybrid functional (sc‐PBE0) with 12.7 % Fock‐exchange provides accurate structural, energetic and electronic properties for both VO 2 phases in the bulk. Therefore, the sc‐PBE0 functional, as implemented the program CRYSTAL17 v1.0.2, [30] is used in this study to calculate surface properties.…”

“…Therefore, the sc‐PBE0 functional, as implemented the program CRYSTAL17 v1.0.2, [30] is used in this study to calculate surface properties. Comparatively small basis sets with respect to the standard pob‐TZVP basis sets, [31] which were applied in our previous studies on VO 2 , [7,29] are used to reduce the computational effort. For Vanadium a modified 86‐411d31G basis set by Harrison et al [32] .…”

The mechanism of semiconductor to metal transition in the hydrogenation of VO2: a density functional theory study

“…The decrease of energy gaps was mainly originated from the down-shift and broadening of the conduction band. 61,65 According to PDOSs, the broadening is due to the decreasing locality of V 3d and O 2p constituting the conduction band with increasing hydrogen concentration from two hydrogen to five hydrogen atoms. When there are more than six hydrogen atoms, the conduction band levels are obviously divided into two groups, and the group near the Fermi level moves to the lower energy with the increase of hydrogen atoms from six to seven, resulting in the further decrease of the band gap (Fig.…”

In Situ Conversion of Metal–Organic Frameworks into VO2–V3S4 Heterocatalyst Embedded Layered Porous Carbon as an “All‐in‐One” Host for Lithium–Sulfur Batteries

“…First‐principles calculations were performed using the DFT with the projector augmented wave method [ 47 ] and generalized gradient approximation of the Perdew–Burke–Ernzerhof functional [ 48 ] as implemented in the Vienna Ab initio Simulation Package. [ 49 ] Spin‐polarized calculations were performed and the effective Hubbard U correction (3.4 eV for V [ 50 ] ) was used for the GGA + U methods. [ 51 ] The vdW interactions were corrected using the Grimme method (DFT‐D3).…”