Spatial Dimensionality Dependence of Heterogeneity, Breakdown of the Stokes-Einstein Relation and Fragility of a Model Glass-Forming Liquid

Monoj Adhikari; Smarajit Karmakar; Srikanth Sastry

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arXiv · 2108.08550

Spatial Dimensionality Dependence of Heterogeneity, Breakdown of the Stokes-Einstein Relation and Fragility of a Model Glass-Forming Liquid

Monoj Adhikari·Smarajit Karmakar·Srikanth Sastry

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Abstract

We investigate the heterogeneity of dynamics, the breakdown of the Stokes-Einstein relation and fragility in a model glass forming liquid, a binary mixture of soft spheres with a harmonic interaction potential, for spatial dimensions from 3 to 8. Dynamical heterogeneity is quantified through the dynamical susceptibility $χ_4$, and the non-Gaussian parameter $α_2$. We find that the fragility, the degree of breakdown of the Stokes-Einstein relation, as well as heterogeneity of dynamics, decrease with increasing spatial dimensionality. We briefly describe the dependence of fragility on density, and use it to resolve an apparent inconsistency with previous results.

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Monoj Adhikari, Smarajit Karmakar, Srikanth Sastry. 2021-08-19. Spatial Dimensionality Dependence of Heterogeneity, Breakdown of the Stokes-Einstein Relation and Fragility of a Model Glass-Forming Liquid. https://arxiv.org/abs/2108.08550

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