An alternative approach to evidence the structural conditioning in the dynamic slowdown in a polymer glass-former

BALBUENA, CRISTIAN; SOULE, EZEQUIEL

JOURNAL OF PHYSICS CONDENSED MATTER

IOP PUBLISHING LTD

Lugar: Londres; Año: 2020 vol. 32

0953-8984

Dynamic slowdown of liquids, leading to a breakdown of Arrhenius behaviorof relaxation and Stokes-Einstein relationship (SER), as the glass transition isapproached, is still not fully understood despite decades of study. They areusually associated to the emergence of dynamic heterogeneity, that is, regionsor clusters of particles that have high or low mobilities. But the physical origin ofthese dynamic heterogeneity, and in particular, the question whether they havea structural origin or they are a purely dynamical phenomenon, is still underdebate. In this work we study through Molecular Dynamics simulations in apolymer model the dynamic slowdown and the breakdown of SER, in connectionwith dynamic susceptibility calculated for an isoconfigurational ensemble, suchthat the effects of structure on dynamics can be discriminated. The onset ofstructure effects on dynamical behavior is found to be coincident with the onsetof slow dynamics and SER breakdown.