Probing large viscosities in glass-formers with nonequilibrium simulations [Physics]
![Probing large viscosities in glass-formers with nonequilibrium simulations [Physics]](/image/eyJ1cmkiOiJodHRwOi8vc3RhY2thZGVtaWMuaGVyb2t1YXBwLmNvbS9pbWFnZT9pbWFnZV9pZD0xOTc1IiwiZm9ybWF0Ijoid2VicCIsInF1YWxpdHkiOjEwMCwibm9DYWNoZSI6dHJ1ZX0=.webp)
For decades, scientists have debated whether supercooled liquids stop flowing below a glass transition temperature
Tg0 or whether motion continues to slow gradually down to zero temperature. Answering this question is challenging because human
time scales set a limit on the largest measurable viscosity, and available data are equally well fit to models with opposite
conclusions. Here, we use short simulations to determine the nonequilibrium shear response of a typical glass-former, squalane.
Fits of the data to an Eyring model allow us to extrapolate predictions for the equilibrium Newtonian viscosity
ηN over a range of pressures and temperatures that change
ηN by 25 orders of magnitude. The results agree with the unusually large set of equilibrium and nonequilibrium experiments on
squalane and extend them to higher
ηN. Studies at different pressures and temperatures are inconsistent with a diverging viscosity at finite temperature. At all
pressures, the predicted viscosity becomes Arrhenius with a single temperature-independent activation barrier at low temperatures
and high viscosities (
ηN>103 Pa
⋅s). Possible experimental tests of our results are outlined.
Publisher URL: http://feedproxy.google.com/~r/Pnas-RssFeedOfEarlyEditionArticles/~3/DNiQxIF6qCk/1705978114.short
DOI: 10.1073/pnas.1705978114
Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.
Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.