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Power laws in pressure-induced structural change of glasses.

ABSTRACT: Many glasses exhibit fractional power law (FPL) between the mean atomic volume v_a and the first diffraction peak position q₁, i.e. [Formula: see text] with d???2.5 deviating from the space dimension D?=?3, under compression or composition change. What structural change causes such FPL and whether the FPL and d are universal remain controversial. Here our simulations show that the FPL holds in both two- and three-dimensional glasses under compression when the particle interaction has two length scales which can induce nonuniform local deformations. The exponent d is not universal, but varies linearly with the deformable part of soft particles. In particular, we reveal an unexpected crossover regime with d?>?D from crystal behavior (d?=?D) to glass behavior (d?

SUBMITTER: Zhang H

PROVIDER: S-EPMC7181815 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Power laws in pressure-induced structural change of glasses.

Zhang Huijun H Qiao Kaiyao K Han Yilong Y

Nature communications 20200424 1

Many glasses exhibit fractional power law (FPL) between the mean atomic volume v<sub>a</sub> and the first diffraction peak position q<sub>1</sub>, i.e. [Formula: see text] with d ≃ 2.5 deviating from the space dimension D = 3, under compression or composition change. What structural change causes such FPL and whether the FPL and d are universal remain controversial. Here our simulations show that the FPL holds in both two- and three-dimensional glasses under compression when the particle intera ...[more]

PMID: 32332710

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