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Inelastic x-ray scattering reveals the ergodic to nonergodic transition of salol, a liquid with local order

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 نشر من قبل Daniele Fioretto
 تاريخ النشر 2019
  مجال البحث فيزياء
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We have studied the high-frequency dynamics of salol by inelastic x-ray scattering over a wide temperature range between 50 and 450 K, across the glass transition. We find that salol efficiently realizes the mechanism of dynamical arrest described by the mode-coupling theory, as manifested by a cusp singularity in the behaviour of the non-ergodicity parameter and a $Q$ dependence of the critical non-ergodicity parameter that is in phase with the static structure factor. These results confront positively the mode-coupling theory with liquids with local order.

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