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arXiv · 1006.0958

Real space investigation of structural changes at the metal-insulator transition in VO2

Serena A. Corr·Daniel P. Shoemaker·Brent C. Melot·Ram Seshadri
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Abstract

Synchrotron X-ray total scattering studies of structural changes in rutile VO2 at the metal-insulator transition temperature of 340 K reveal that monoclinic and tetragonal phases of VO2 coexist in equilibrium, as expected for a first-order phase transition. No evidence for any distinct intermediate phase is seen. Unbiased local structure studies of the changes in V--V distances through the phase transition, using reverse Monte Carlo methods, support the idea of phase coexistence and point to the high degree of correlation in the dimerized low-temperature structure. No evidence for short range V--V correlations that would be suggestive of local dimers is found in the metallic phase.

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Serena A. Corr, Daniel P. Shoemaker, Brent C. Melot, Ram Seshadri. 2010-06-04. Real space investigation of structural changes at the metal-insulator transition in VO2. https://doi.org/10.1103/physrevlett.105.056404

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