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arXiv · 0707.2521

Nonlinear viscoelastic dynamics of nano-confined water

Tai-De Li·Elisa Riedo
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Abstract

The viscoelastic dynamics of nano-confined water is studied by means of atomic force microscopy (AFM). We observe a nonlinear viscoelastic behavior remarkably similar to that widely observed in metastable complex fluids. We show that the origin of the measured nonlinear viscoelasticity in nano-confined water is a strain rate dependent relaxation time and slow dynamics. By measuring the viscoelastic modulus at different frequencies and strains, we find that the intrinsic relaxation time of nano-confined water is in the range 0.1-0.0001 s, orders of magnitude longer than that of bulk water, and comparable to the dielectric relaxation time measured in supercooled water at 170-210 K.

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Tai-De Li, Elisa Riedo. 2007-07-17. Nonlinear viscoelastic dynamics of nano-confined water. https://doi.org/10.1103/physrevlett.100.106102

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