Weak correlations between local density and dynamics near the glass transition.

نویسندگان

  • J C Conrad
  • F W Starr
  • D A Weitz
چکیده

We perform experiments on two different dense colloidal suspensions with confocal microscopy to probe the relationship between local structure and dynamics near the glass transition. We calculate the Voronoi volume for our particles and show that this quantity is not a universal probe of glassy structure for all colloidal suspensions. We correlate the Voronoi volume to displacement and find that these quantities are only weakly correlated. We observe qualitatively similar results in a simulation of a polymer melt. These results suggest that the Voronoi volume does not predict dynamical behavior in experimental colloidal suspensions; a purely structural approach based on local single particle volume likely cannot describe the colloidal glass transition.

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عنوان ژورنال:
  • The journal of physical chemistry. B

دوره 109 45  شماره 

صفحات  -

تاریخ انتشار 2005