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Reversal of the Temperature Dependence of Hydrophobic Hydration in Supercooled Water.

ABSTRACT: Using simulations and theory, we examine the enthalpy and entropy of hydrophobic hydration which exhibit minima in supercooled water, contrasting with the monotonically increasing temperature dependence traditionally ascribed to these properties. The enthalpy/entropy minima are marked by a negative to positive sign change in the heat capacity at a size-dependent reversal temperature. A Gaussian fluctuation theory accurately captures the reversal temperature, tracing it to water's distinct thermal expansivity and compressibility influenced by its metastable liquid-liquid critical point.

SUBMITTER: Ashbaugh HS

PROVIDER: S-EPMC8419862 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Reversal of the Temperature Dependence of Hydrophobic Hydration in Supercooled Water.

Ashbaugh Henry S HS

The journal of physical chemistry letters 20210826 34

Using simulations and theory, we examine the enthalpy and entropy of hydrophobic hydration which exhibit minima in supercooled water, contrasting with the monotonically increasing temperature dependence traditionally ascribed to these properties. The enthalpy/entropy minima are marked by a negative to positive sign change in the heat capacity at a size-dependent reversal temperature. A Gaussian fluctuation theory accurately captures the reversal temperature, tracing it to water's distinct therma ...[more]

PMID: 34435491

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