Synthesis and Structure
Following the method described by Berzelius, VO2 is prepared by comproportionation of vanadium(III) oxide and vanadium(V) oxide:
- V2O5 + V2O3 → 2 VO2
At room temperature VO2 has a distorted rutile structure with shorter distances between pairs of V atoms indicating metal-metal bonding. Above 68 °C the structure changes to an undistorted rutile structure and the metal-metal bonds are broken causing an increase in electrical conductivity and magnetic susceptibility as the bonding electrons are "released". The origin of this metal to insulator transition remains controversial and is of interest in condensed matter physics.
Read more about this topic: Vanadium(IV) Oxide
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