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Entropy from state probabilities: hydration entropy of cations.

ABSTRACT: Entropy is an important energetic quantity determining the progression of chemical processes. We propose a new approach to obtain hydration entropy directly from probability density functions in state space. We demonstrate the validity of our approach for a series of cations in aqueous solution. Extensive validation of simulation results was performed. Our approach does not make prior assumptions about the shape of the potential energy landscape and is capable of calculating accurate hydration entropy values. Sampling times in the low nanosecond range are sufficient for the investigated ionic systems. Although the presented strategy is at the moment limited to systems for which a scalar order parameter can be derived, this is not a principal limitation of the method. The strategy presented is applicable to any chemical system where sufficient sampling of conformational space is accessible, for example, by computer simulations.

SUBMITTER: Huber RG

PROVIDER: S-EPMC3668459 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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Entropy from state probabilities: hydration entropy of cations.

Huber Roland G RG Fuchs Julian E JE von Grafenstein Susanne S Laner Monika M Wallnoefer Hannes G HG Abdelkader Nejma N Kroemer Romano T RT Liedl Klaus R KR

The journal of physical chemistry. B 20130520 21

Entropy is an important energetic quantity determining the progression of chemical processes. We propose a new approach to obtain hydration entropy directly from probability density functions in state space. We demonstrate the validity of our approach for a series of cations in aqueous solution. Extensive validation of simulation results was performed. Our approach does not make prior assumptions about the shape of the potential energy landscape and is capable of calculating accurate hydration e ...[more]

PMID: 23651109

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Entropy from state probabilities: hydration entropy of cations.

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Entropy from state probabilities: hydration entropy of cations.

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