| Abstract
| - We report a significantly stronger suppression of the phonon contribution to the thermal conductivity in $\chem{VO}$x than can be accounted for by disorder of the 16% atomic vacancies present in $\chem{VO}$. Since the transition from localized to itinerant electronic behavior is first order and has been shown to be characterized by bond length fluctuations in several transition-metal oxides with the perovskite structure, we propose that cooperative $\chem{V\tx{-}V}$ bond length fluctuations play a role in $\chem{VO}$ similar to the $\chem{M\tx{-}O}$ bond length fluctuations in the perovskites. This model is able to account for the strong suppression of the thermal conductivity, the existence of a pseudogap confirmed by thermoelectric power, an anomalously large Debye-Waller factor, the temperature dependence of the magnetic susceptibility, and the inability to order atomic vacancies in $\chem{VO}$.
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