Metal-Insulator Phase Transition in Quasi-One-Dimensional VO₂ Structures

Figure 1

(a) The crystal structures of the high-temperature tetragonal rutile (R, space group P4₂/mnm) and low-temperature monoclinic (M1, space group P2₁/c) phases of VO₂, with the equivalent direction of . V–V distances are highlighted: the R phase with regular VO₆ octahedron exhibits uniform V–V distances of 2.86 Å and the M1 phase with distorted VO₆ octahedron exhibits alternating V–V distances of 2.65 and 3.12 Å. (b) A schematic diagram of the molecular orbital structures of the M1 and R phases of VO₂ (left side: the undistorted metallic phase of VO₂, right side: the distorted insulating phase of VO₂). Panels (a) and (b) adapted with permission from [23] and [22], respectively.

(a)

(b)