Neglecting polydispersity degrades propensity measurements in supercooled liquids

We conduct molecular dynamics simulations of a bidisperse Kob-Andersen (KA) glass former, modified to add in additional polydispersity. The original KA system is known exhibit dynamical heterogeneity. Prior work defined propensity, the mean motion particle averaged over reconstructing initial positions all particles but with randomized velocities. existence propensity shows that structure and are connected. In this paper, we study systems which mimic problems would be encountered measuring colloidal where polydisperse (they have slight size variations). polydispersity by altering into quartet consisting both slightly larger smaller than parent system. then introduce errors reconstruction mistakes one might make experiment. degrade measurement, some cases nearly completely; no longer has an isoconfigurational ensemble any useful sense. Our results show sample suitable for measurements provided avoids mistakes.